Efficacy and Safety of Appropriate Shocks and Antitachycardia Pacing in Transvenous and Subcutaneous Implantable Defibrillators: Analysis of All Appropriate Therapy in the PRAETORIAN Trial.

BACKGROUND: The PRAETORIAN trial (A Prospective, Randomized Comparison of Subcutaneous and Transvenous Implantable Cardioverter Defibrillator Therapy) showed noninferiority of subcutaneous implantable cardioverter defibrillator (S-ICD) compared with transvenous implantable cardioverter defibrillator (TV-ICD) with regard to inappropriate shocks and complications. In contrast to TV-ICD, S-ICD cannot provide antitachycardia pacing for monomorphic ventricular tachycardia. This prespecified secondary analysis evaluates appropriate therapy and whether antitachycardia pacing reduces the number of appropriate shocks. METHODS: The PRAETORIAN trial was an international, investigator-initiated randomized trial that included patients with an indication for implantable cardioverter defibrillator (ICD) therapy. Patients with previous ventricular tachycardia <170 bpm or refractory recurrent monomorphic ventricular tachycardia were excluded. In 39 centers, 849 patients were randomized to receive an S-ICD (n=426) or TV-ICD (n=423) and were followed for a median of 49.1 months. ICD programming was mandated by protocol. Appropriate ICD therapy was defined as therapy for ventricular arrhythmias. Arrhythmias were classified as discrete episodes and storm episodes (≥3 episodes within 24 hours). Analyses were performed in the modified intention-to-treat population. RESULTS: In the S-ICD group, 86 of 426 patients received appropriate therapy, versus 78 of 423 patients in the TV-ICD group, during a median follow-up of 52 months (48-month Kaplan-Meier estimates 19.4% and 17.5%; P=0.45). In the S-ICD group, 83 patients received at least 1 shock, versus 57 patients in the TV-ICD group (48-month Kaplan-Meier estimates 19.2% and 11.5%; P=0.02). Patients in the S-ICD group had a total of 254 shocks, compared with 228 shocks in the TV-ICD group (P=0.68). First shock efficacy was 93.8% in the S-ICD group and 91.6% in the TV-ICD group (P=0.40). The first antitachycardia pacing attempt successfully terminated 46% of all monomorphic ventricular tachycardias, but accelerated the arrhythmia in 9.4%. Ten patients with S-ICD experienced 13 electrical storms, versus 18 patients with TV-ICD with 19 electrical storms. Patients with appropriate therapy had an almost 2-fold increased relative risk of electrical storms in the TV-ICD group compared with the S-ICD group (P=0.05). CONCLUSIONS: In this trial, no difference was observed in shock efficacy of S-ICD compared with TV-ICD. Although patients in the S-ICD group were more likely to receive an ICD shock, the total number of appropriate shocks was not different between the 2 groups. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01296022.

Device-related complications in subcutaneous versus transvenous ICD: a secondary analysis of the PRAETORIAN trial.

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) is developed to overcome lead-related complications and systemic infections, inherent to transvenous ICD (TV-ICD) therapy. The PRAETORIAN trial demonstrated that the S-ICD is non-inferior to the TV-ICD with regard to the combined primary endpoint of inappropriate shocks and complications. This prespecified secondary analysis evaluates all complications in the PRAETORIAN trial. METHODS AND RESULTS: The PRAETORIAN trial is an international, multicentre, randomized trial in which 849 patients with an indication for ICD therapy were randomized to receive an S- ICD (N = 426) or TV-ICD (N = 423) and followed for a median of 49 months. Endpoints were device-related complications, lead-related complications, systemic infections, and the need for invasive interventions. Thirty-six device-related complications occurred in 31 patients in the S-ICD group of which bleedings were the most frequent. In the TV-ICD group, 49 complications occurred in 44 patients of which lead dysfunction was most frequent (HR: 0.69; P = 0.11). In both groups, half of all complications were within 30 days after implantation. Lead-related complications and systemic infections occurred significantly less in the S-ICD group compared with the TV-ICD group (P < 0.001, P = 0.03, respectively). Significantly more complications required invasive interventions in the TV-ICD group compared with the S-ICD group (8.3% vs. 4.3%, HR: 0.59; P = 0.047). CONCLUSION: This secondary analysis shows that lead-related complications and systemic infections are more prevalent in the TV-ICD group compared with the S-ICD group. In addition, complications in the TV-ICD group were more severe as they required significantly more invasive interventions. This data contributes to shared decision-making in clinical practice.

Clinical and cardiac characteristics of COVID-19 mortalities in a diverse New York City Cohort.

INTRODUCTION: Electrocardiographic characteristics in COVID-19-related mortality have not yet been reported, particularly in racial/ethnic minorities. METHODS AND RESULTS: We reviewed demographics, laboratory and cardiac tests, medications, and cardiac rhythm proximate to death or initiation of comfort care for patients hospitalized with a positive SARS-CoV-2 reverse-transcriptase polymerase chain reaction in three New York City hospitals between March 1 and April 3, 2020 who died. We described clinical characteristics and compared factors contributing toward arrhythmic versus nonarrhythmic death. Of 1258 patients screened, 133 died and were enrolled. Of these, 55.6% (74/133) were male, 69.9% (93/133) were racial/ethnic minorities, and 88.0% (117/133) had cardiovascular disease. The last cardiac rhythm recorded was VT or fibrillation in 5.3% (7/133), pulseless electrical activity in 7.5% (10/133), unspecified bradycardia in 0.8% (1/133), and asystole in 26.3% (35/133). Most 74.4% (99/133) died receiving comfort measures only. The most common abnormalities on admission electrocardiogram included abnormal QRS axis (25.8%), atrial fibrillation/flutter (14.3%), atrial ectopy (12.0%), and right bundle branch block (11.9%). During hospitalization, an additional 17.6% developed atrial ectopy, 14.7% ventricular ectopy, 10.1% atrial fibrillation/flutter, and 7.8% a right ventricular abnormality. Arrhythmic death was confirmed or suspected in 8.3% (11/133) associated with age, coronary artery disease, asthma, vasopressor use, longer admission corrected QT interval, and left bundle branch block (LBBB). CONCLUSIONS: Conduction, rhythm, and electrocardiographic abnormalities were common during COVID-19-related hospitalization. Arrhythmic death was associated with age, coronary artery disease, asthma, longer admission corrected QT interval, LBBB, ventricular ectopy, and usage of vasopressors. Most died receiving comfort measures.

The initial U.S. experience with the Tempo active fixation temporary pacing lead in structural heart interventions.

OBJECTIVES: This multicenter retrospective study of the initial U.S. experience evaluated the safety and efficacy of temporary cardiac pacing with the Tempo® Temporary Pacing Lead. BACKGROUND: Despite increasing use of temporary cardiac pacing with the rapid growth of structural heart procedures, temporary pacing leads have not significantly improved. The Tempo lead is a new temporary pacing lead with a soft tip intended to minimize the risk of perforation and a novel active fixation mechanism designed to enhance lead stability. METHODS: Data from 269 consecutive structural heart procedures were collected. Outcomes included device safety (absence of clinically significant cardiac perforation, new pericardial effusion, or sustained ventricular arrhythmia) and efficacy (clinically acceptable pacing thresholds with successful pace capture throughout the index procedure). Postprocedure practices and sustained lead performance were also analyzed. RESULTS: The Tempo lead was successfully positioned in the right ventricle and achieved pacing in 264 of 269 patients (98.1%). Two patients (0.8%) experienced loss of pace capture. Procedural mean pace capture threshold (PCT) was 0.7 ± 0.8 mA. There were no clinically significant perforations, pericardial effusions, or sustained device-related arrhythmias. The Tempo lead was left in place postprocedure in 189 patients (71.6%) for mean duration of 43.3 ± 0.7 hr (range 2.5-221.3 hr) with final PCT of 0.84 ± 1.04 mA (n = 80). Of these patients, 84.1% mobilized out of bed with no lead dislodgment. CONCLUSION: The Tempo lead is safe and effective for temporary cardiac pacing for structural heart procedures, provides stable peri and postprocedural pacing and allows mobilization of patients who require temporary pacing leads.

New-onset left bundle branch block after transcatheter aortic valve replacement is associated with adverse long-term clinical outcomes in intermediate-risk patients: an analysis from the PARTNER II trial.

AIMS: Transcatheter aortic valve replacement (TAVR) is now an established therapy for intermediate-risk surgical candidates with symptomatic, severe aortic stenosis. The clinical impact of new-onset left bundle branch block (LBBB) after TAVR remains controversial and has not been studied in intermediate-risk patients. We therefore sought to analyse outcomes associated with new LBBB in a large cohort of intermediate-risk patients treated with TAVR. METHODS AND RESULTS: A total of 2043 patients underwent TAVR in the PARTNER II trial and S3 intermediate-risk registry and survived to hospital discharge. Patients were excluded from the current analysis due to baseline conduction disturbances, pre-existing permanent pacemaker (PPM), and new PPM during the index hospitalization. Clinical outcomes at 2 years were compared between patients with and without persistent, new-onset LBBB at hospital discharge, and multivariable analysis was performed to identify predictors of mortality. Among 1179 intermediate-risk patients, new-onset LBBB at discharge occurred in 179 patients (15.2%). Patients with new LBBB were similar to those without except for more frequent diabetes and more frequent treatment with SAPIEN 3 vs. SAPIEN XT. At 2 years, new LBBB was associated with increased rates of all-cause mortality (19.3% vs. 10.8%, P = 0.002), cardiovascular mortality (16.2% vs. 6.5%, P < 0.001), rehospitalization, and new PPM implantation. By multivariable analysis, new LBBB remained an independent predictor of 2-year all-cause [hazard ratio (HR) 1.98, 95% confidence interval (95% CI) 1.33, 2.96; P < 0.001] and cardiovascular (HR 2.66 95% CI 1.67, 4.24; P < 0.001) mortality. New LBBB was also associated with worse left ventricular systolic function at 1 and 2-year follow-up. CONCLUSIONS: In a large cohort of intermediate-risk patients from the PARTNER II trial and registry, persistent, new-onset LBBB occurred in 15.2% of patients without baseline conduction disturbances or pacemaker. New LBBB was associated with adverse clinical outcomes at 2 years, including all-cause and cardiovascular mortality, rehospitalization, new pacemaker implantation, and worsened left ventricular systolic function. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov #NCT01314313 and NCT03222128.

Recurrent atrial fibrillation/flutter detection after ablation or cardioversion using the AliveCor KardiaMobile device: iHEART results.

OBJECTIVE: This study evaluated the impact of daily ECG (electrocardiogram) self-recordings on time to documented recurrent atrial fibrillation (AF) or atrial flutter (AFL) and time to treatment of recurrent arrhythmia in patients undergoing catheter radiofrequency ablation (RFA) or direct current cardioversion (DCCV) for AF/AFL. BACKGROUND: AF recurrence rates after RFA and DCCV are 20% to 45% and 60% to 80%, respectively. Randomized trials comparing mobile ECG devices to standard of care have not been performed in an AF/AFL population after treatment. METHODS: Of 262 patients consented, 238 were randomized to either standard of care (123) or to receive the iHEART intervention (115). Patients in the intervention group were provided with and trained to use an AliveCor KardiaMobile ECG monitor, and were instructed to take and transmit daily ECG recordings. Data were collected from transmitted ECG recordings and patients' electronic health records. RESULTS: In a multivariate Cox model, the likelihood of recurrence detection was greater in the intervention group (hazard ratio = 1.56, 95% confidence interval [CI]: 1.06-2.30, P = .024). Hazard ratios did not differ significantly for RFA and DCCV procedures. Recurrence during the first month after ablation strongly predicted later recurrence (hazard ratio = 4.53, 95% CI: 2.05-10.00, P = .0006). Time from detection to treatment was shorter for the control group (hazard ratio = 0.33, 95% CI: 0.57-2.92, P < .0001). CONCLUSIONS: The use of mobile ECG self-recording devices allows for earlier detection of AF/AFL recurrence and may empower patients to engage in shared health decision-making.

Sex, adverse cardiac events, and infarct size in anterior myocardial infarction: an analysis of intracoronary abciximab and aspiration thrombectomy in patients with large anterior myocardial infarction (INFUSE-AMI).

BACKGROUND: Women are more likely than men to experience adverse cardiac events after ST-elevation myocardial (STEMI). Whether differences in infarct size or reperfusion contribute to sex differences in outcomes is unknown. METHODS: We compared baseline and procedural characteristics, angiographic and electrocardiographic indices of reperfusion, microvascular obstruction, infarct size, and clinical outcomes in 118 women and 334 men with anterior STEMI enrolled in the INFUSE-AMI randomized trial of intralesion abciximab and aspiration thrombectomy (NCT00976521). Infarct size was assessed by cardiac magnetic resonance imaging at 30 days, and clinical end points were adjudicated by an independent committee. RESULTS: Women were older, were more commonly affected by hypertension and renal impairment, and had a 50.5-minute longer delay to reperfusion. There were no differences in infarct size, microvascular obstruction, or reperfusion success. At 30 days, major adverse cardiac events (MACE), defined as death, reinfarction, new-onset severe heart failure, or rehospitalization for heart failure, were more common in women (11.1% vs 5.4%, hazard ratio 2.09, 95% CI 1.03-4.27, P = .04). After multivariable adjustment, age, but not sex or time to reperfusion, was an independent predictor of MACE. CONCLUSIONS: In the INFUSE-AMI randomized trial, women with anterior STEMI experienced a higher rate of MACE, attributable to older age. Despite longer delay from symptom onset to reperfusion therapy, there was no difference between women and men in infarct size or reperfusion success.

Clinical implications of new-onset left bundle branch block after transcatheter aortic valve replacement: analysis of the PARTNER experience.

AIMS: Cardiac conduction disturbances, including a left bundle branch block (LBBB), occur frequently following transcatheter aortic valve replacement (TAVR) and may be associated with adverse clinical events. This analysis examines the incidence and implications of new onset, persistent LBBB in patients undergoing TAVR with a balloon-expandable valve. METHODS AND RESULTS: Patients undergoing TAVR in the Placement of Aortic Transcatheter Valves (PARTNER) trial and continued access registries with baseline and discharge/7-day electrocardiograms were included. Prior permanent pacemaker implantation (PPI) and baseline intraventricular conduction abnormalities were exclusion criteria. Predictors of new LBBB were identified and outcomes compared between patients with and without new LBBB. New LBBB occurred in 121 of 1151 (10.5%) patients and persisted in more than half at 6 months to 1 year. The only predictor of new LBBB was prior coronary artery bypass grafting. New LBBB was not associated with significant differences in 1-year mortality, cardiovascular mortality, repeat hospitalization, stroke, or myocardial infarction. However, it was associated with increased PPI during hospitalization (8.3 vs 2.8%, P = 0.005) and from discharge to 1 year (4.7 vs. 1.5%, P = 0.01). The ejection fraction failed to improve after TAVR in patients with new LBBB and remained lower at 6 months to 1 year (52.8 vs. 58.1%, P < 0.001). CONCLUSION: Persistent, new-onset LBBB occurred in 10.5% of patients without intraventricular baseline conduction who underwent TAVR in the PARTNER experience. New LBBB was not associated with death, repeat hospitalization, stroke, or myocardial infarction at 1 year, but was associated with a higher rate of PPI and failure of left ventricular ejection fraction to improve.

Predictors and 5-Year Clinical Outcomes of Pacemaker After TAVR: Analysis From the PARTNER 2 SAPIEN 3 Registries.

BACKGROUND: Conduction disturbances requiring a permanent pacemaker (PPM) are a frequent complication of transcatheter aortic valve replacement (TAVR) with few reports of rates, predictors, and long-term clinical outcomes following implantation of the third-generation, balloon-expandable SAPIEN 3 (S3) transcatheter heart valve (THV). OBJECTIVES: The aim of this study was to investigate the rates, predictors, and long-term clinical outcomes of PPM implantation following TAVR with the S3 THV. METHODS: The current study included 857 patients in the PARTNER 2 S3 registries with intermediate and high surgical risk without prior PPM, and investigated predictors and 5-year clinical outcomes of new PPM implanted within 30 days of TAVR. RESULTS: Among 857 patients, 107 patients (12.5%) received a new PPM within 30 days after TAVR. By multivariable analysis, predictors of PPM included increased age, pre-existing right bundle branch block, larger THV size, greater THV oversizing, moderate or severe annulus calcification, and implantation depth >6 mm. At 5 years (median follow-up 1,682.0 days [min 2.0 days, max 2,283.0 days]), new PPM was not associated with increased rates of all-cause mortality (Adj HR: 1.20; 95% CI: 0.85-1.70; P = 0.30) or repeat hospitalization (Adj HR: 1.22; 95% CI: 0.67-2.21; P = 0.52). Patients with new PPM had a decline in left ventricular ejection fraction at 1 year that persisted at 5 years (55.1 ± 2.55 vs 60.4 ± 0.65; P = 0.02). CONCLUSIONS: PPM was required in 12.5% of patients without prior PPM who underwent TAVR with a SAPIEN 3 valve in the PARTNER 2 S3 registries and was not associated with worse clinical outcomes, including mortality, at 5 years. Modifiable factors that may reduce the PPM rate include bioprosthetic valve oversizing, prosthesis size, and implantation depth.

Complementary prognostic utility of myocardial blush grade and ST-segment resolution after primary percutaneous coronary intervention: analysis from the HORIZONS-AMI trial.

BACKGROUND: Both ST-segment resolution (STR) and myocardial blush grade (MBG) have prognostic utility after primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction. We sought to clarify how frequently MBG and STR provide discordant measures of reperfusion success and to determine the independent prognostic significance of each on long-term outcomes. METHODS: In HORIZONS-AMI, core laboratory measures of both MBG and STR were assessed in 2,367 patients undergoing primary PCI. Four groups were identified based on MBG (grades 2/3 vs 0/1) and STR (≥50% vs <50%). A multivariable model identified predictors of death and major adverse cardiac events at 3 years. RESULTS: Myocardial blush grade 2/3 was achieved in 77.7% of patients, and STR ≥50% was achieved in 75.1% of patients. Myocardial blush grade and STR were discordant in 765 patients (30.9%). By multivariable analysis, MBG 2/3 compared with 0/1 was an independent predictor of lower mortality at 3 years (4.4% vs 8.4%, adjusted hazard ratio [HR] = 0.57 [0.39, 0.82], P = .003). In contrast, STR ≥50% compared with <50% was not associated with mortality (5.1% vs 5.9%, adjusted HR = 1.11 [0.68, 1.56], P = .89). However, repeated revascularization at 3 years was less frequent when STR ≥50% (12.4% vs 17.6%, adjusted HR = 0.74 [0.58, 0.95], P = .02). In contrast, MBG 2/3 vs 0/1 was not associated with reduced repeated revascularization (13.6% vs 14.1%, adjusted HR = 1.02 [0.79, 1.33], P = .85). CONCLUSIONS: In HORIZONS-AMI, MBG and STR after primary PCI were concordant in only 70% of patients and provided complementary prognostic information. Myocardial blush grade predicted long-term survival, whereas STR predicted freedom from repeated revascularization.

Anti-N-methyl-D-aspartate receptor encephalitis: an emerging cause of centrally mediated sinus node dysfunction.

AIMS: Anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) is a recently recognized form of autoimmune encephalitis that typically affects young women, often as a paraneoplastic syndrome related to ovarian teratoma. Clinical features include psychiatric and neurological disturbances, central hypoventilation, autonomic instability, and cardiac dysrhythmias. The prevalence, nature, and outcomes of cardiac dysrhythmias in patients with NMDARE have not been well described. METHODS AND RESULTS: Records of 10 consecutive patients with NMDARE were reviewed to obtain clinical, laboratory, echocardiographic, electrocardiographic, and radiological data. Patients were all female with an average age of 23 ± 5.5 years. Echocardiograms revealed structurally normal hearts with the exception of mild left ventricular hypertrophy in two cases. Eight patients had inappropriate sinus tachycardia. Six patients developed significant sinus bradycardia, which included periods of sinus arrest in four cases. Five patients manifested both sinus bradycardia and tachycardia. Bradycardia was often triggered by identifiable vagal stimuli. Temporary pacing was instituted in three patients, but permanent pacing was not required in any of the patients. Magnetic resonance imaging (MRI) scans revealed mesial temporal abnormalities in nine patients. In all cases, the dysrhythmias resolved with treatment of the underlying immune disorder with immunotherapy and/or teratoma resection. There was no evidence of dysrhythmia recurrence in any patient at follow-up. CONCLUSION: Anti-N-methyl-D-aspartate receptor encephalitis is a recently recognized cause of autoimmune encephalitis with a predilection to cause severe sinus node abnormalities. Temporary pacing is occasionally required, but permanent pacing appears to be unnecessary. An analysis of the clinical syndrome coupled with MRI and experimental data may offer insight into central mechanisms of heart rate regulation.

Intracoronary abciximab and aspiration thrombectomy in patients with large anterior myocardial infarction: the INFUSE-AMI randomized trial.

CONTEXT: Thrombus embolization during percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI) is common and results in suboptimal myocardial perfusion and increased infarct size. Two strategies proposed to reduce distal embolization and improve outcomes after primary PCI are bolus intracoronary abciximab and manual aspiration thrombectomy. OBJECTIVE: To determine whether bolus intracoronary abciximab, manual aspiration thrombectomy, or both reduce infarct size in high-risk patients with STEMI. DESIGN, SETTING, AND PATIENTS: Between November 28, 2009, and December 2, 2011, 452 patients presenting at 37 sites in 6 countries within 4 hours of STEMI due to proximal or mid left anterior descending artery occlusion undergoing primary PCI with bivalirudin anticoagulation were randomized in an open-label, 2 x 2 factorial design to bolus intracoronary abciximab delivered locally at the infarct lesion site vs no abciximab and to manual aspiration thrombectomy vs no thrombectomy. INTERVENTIONS: A 0.25-mg/kg bolus of abciximab was administered at the site of the infarct lesion via a local drug delivery catheter. Manual aspiration thrombectomy was performed with a 6 F aspiration catheter. MAIN OUTCOME MEASURES: Primary end point: infarct size (percentage of total left ventricular mass) at 30 days assessed by cardiac magnetic resonance imaging (cMRI) in the abciximab vs no abciximab groups (pooled across the aspiration randomization); major secondary end point: 30-day infarct size in the aspiration vs no aspiration groups (pooled across the abciximab randomization). RESULTS: Evaluable cMRI results at 30 days were present in 181 and 172 patients randomized to intracoronary abciximab vs no abciximab, respectively, and in 174 and 179 patients randomized to manual aspiration vs no aspiration, respectively. Patients randomized to intracoronary abciximab compared with no abciximab had a significant reduction in 30-day infarct size (median, 15.1%; interquartile range [IQR], 6.8%-22.7%; n = 181, vs 17.9% [IQR, 10.3%-25.4%]; n = 172; P = .03). Patients randomized to intracoronary abciximab also had a significant reduction in absolute infarct mass (median, 18.7 g [IQR, 7.4-31.3 g]; n = 184, vs 24.0 g [IQR, 12.1-34.2 g]; n = 175; P = .03) but not abnormal wall motion score (median, 7.0 [IQR, 2.0-10.0]; n = 188, vs 8.0 [IQR, 3.0-10.0]; n = 184; P = .08). Patients randomized to aspiration thrombectomy vs no aspiration had no significant difference in infarct size at 30 days (median, 17.0% [IQR, 9.0%-22.8%]; n = 174, vs 17.3% [IQR, 7.1%-25.5%]; n = 179; P = .51), absolute infarct mass (median, 20.3 g [IQR, 9.7-31.7 g]; n = 178, vs 21.0 g [IQR, 9.1-34.1 g]; n = 181; P = .36), or abnormal wall motion score (median, 7.5 [IQR, 2.0-10.0]; n = 186, vs 7.5 [IQR, 2.0-10.0]; n = 186; P = .89). CONCLUSION: In patients with large anterior STEMI presenting early after symptom onset and undergoing primary PCI with bivalirudin anticoagulation, infarct size at 30 days was significantly reduced by bolus intracoronary abciximab delivered to the infarct lesion site but not by manual aspiration thrombectomy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00976521.

Predictors of atrial fibrillation on implantable cardiac monitoring for cryptogenic stroke.

BACKGROUND: Since the CRYSTAL-AF trial, implantation and usage of implantable loop recorder (ICM) after cryptogenic stroke (CS) for detection of atrial fibrillation (AF) has increased. However, it is unclear which CS patients would most benefit from long term ICM monitoring. This study aims to determine the risk factors in patients that would confer maximum benefit from ICM placement following CS. METHODS: A Columbia University Institutional Review Board (IRB) approved retrospective analysis of medical records of 125 patients with CS followed by implantation of ICM was evaluated. Univariable and multivariable time-to-event analyses were performed on demographics, hours of activity and variability (HRV), stroke location, thrombosis etiology, and CHA2DS2 - VASc score. The primary outcome was presence of ICM-detected AF defined as AF lasting at least 2 min. RESULTS: One hundred twenty-five patients (mean 67.6 years ± 2.4 years, 60% male) were followed for at least 3 months. Twenty-two patients (18%) were found to have clinically verified detected AF; median of time to detection was 95 days. Upon univariable demographic analysis followed by multivariable Cox regression analysis, individuals with age 75 or older (HR: 3.987, p = 0.0046) or LVEF 40% and lower (HR: 3.056, p = 0.0213) had significantly higher risk of AF. Diabetics also had a lower AF detection in multivariable analysis (HR: 0.128, p = 0.0466). CONCLUSIONS: Age 75 or older and LVEF ≤40% were the factors on multivariable analysis that predicted AF detection. Diabetes is a possible significant factor which should be evaluated further. CHA2DS2 - VASc score was notably not predictive of AF detected on ICM.

Atrial Fibrillation Is Associated With Mortality in Intermediate Surgical Risk Patients With Severe Aortic Stenosis: Analyses From the PARTNER 2A and PARTNER S3i Trials.

Background The impact of atrial fibrillation (AF) in intermediate surgical risk patients with severe aortic stenosis who undergo either transcatheter or surgical aortic valve replacement (AVR) is not well established. Methods and Results Data were assessed in 2663 patients from the PARTNER (Placement of Aortic Transcatheter Valve) 2A or S3i trials. Analyses grouped patients into 3 categories according to their baseline and discharge rhythms (ie, sinus rhythm [SR]/SR, SR/AF, or AF/AF). Among patients with transcatheter AVR (n=1867), 79.2% had SR/SR, 17.6% had AF/AF, and 3.2% had SR/AF. Among patients with surgical AVR (n=796), 71.7% had SR/SR, 14.1% had AF/AF, and 14.2% had SR/AF. Patients with transcatheter AVR in AF at discharge had increased 2-year mortality (SR/AF versus SR/SR; hazard ratio [HR], 2.73; 95% CI, 1.68-4.44; P<0.0001; AF/AF versus SR/SR; HR, 1.56; 95% CI, 1.16-2.09; P=0.003); patients with SR/AF also experienced increased 2-year mortality relative to patients with AF/AF (HR, 1.77; 95% CI, 1.04-3.00; P=0.03). For patients with surgicalAVR, the presence of AF at discharge was also associated with increased 2-year mortality (SR/AF versus SR/SR; HR, 1.93; 95% CI, 1.25-2.96; P=0.002; and AF/AF versus SR/SR; HR, 1.67; 95% CI, 1.06-2.63; P=0.027). Rehospitalization and persistent advanced heart failure symptoms were also more common among patients with transcatheter AVR and surgical AVR discharged in AF, and major bleeding was more common in the transcatheter AVR cohort. Conclusions The presence of AF at discharge in patients with intermediate surgical risk aortic stenosis was associated with worse outcomes-especially in patients with baseline SR-including increased all-cause mortality at 2-year follow-up. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01314313 and NCT03222128.

Cardiac Corrected QT Interval Changes Among Patients Treated for COVID-19 Infection During the Early Phase of the Pandemic.

Importance: Critical illness, a marked inflammatory response, and viruses such as SARS-CoV-2 may prolong corrected QT interval (QTc). Objective: To evaluate baseline QTc interval on 12-lead electrocardiograms (ECGs) and ensuing changes among patients with and without COVID-19. Design, Setting, and Participants: This cohort study included 3050 patients aged 18 years and older who underwent SARS-CoV-2 testing and had ECGs at Columbia University Irving Medical Center from March 1 through May 1, 2020. Patients were analyzed by treatment group over 5 days, as follows: hydroxychloroquine with azithromycin, hydroxychloroquine alone, azithromycin alone, and neither hydroxychloroquine nor azithromycin. ECGs were manually analyzed by electrophysiologists masked to COVID-19 status. Multivariable modeling evaluated clinical associations with QTc prolongation from baseline. Exposures: COVID-19, hydroxychloroquine, azithromycin. Main Outcomes and Measures: Mean QTc prolongation, percentage of patients with QTc of 500 milliseconds or greater. Results: A total of 965 patients had more than 2 ECGs and were included in the study, with 561 (58.1%) men, 198 (26.2%) Black patients, and 191 (19.8%) aged 80 years and older. There were 733 patients (76.0%) with COVID-19 and 232 patients (24.0%) without COVID-19. COVID-19 infection was associated with significant mean QTc prolongation from baseline by both 5-day and 2-day multivariable models (5-day, patients with COVID-19: 20.81 [95% CI, 15.29 to 26.33] milliseconds; P < .001; patients without COVID-19: -2.01 [95% CI, -17.31 to 21.32] milliseconds; P = .93; 2-day, patients with COVID-19: 17.40 [95% CI, 12.65 to 22.16] milliseconds; P < .001; patients without COVID-19: 0.11 [95% CI, -12.60 to 12.81] milliseconds; P = .99). COVID-19 infection was independently associated with a modeled mean 27.32 (95% CI, 4.63-43.21) millisecond increase in QTc at 5 days compared with COVID-19-negative status (mean QTc, with COVID-19: 450.45 [95% CI, 441.6 to 459.3] milliseconds; without COVID-19: 423.13 [95% CI, 403.25 to 443.01] milliseconds; P = .01). More patients with COVID-19 not receiving hydroxychloroquine and azithromycin had QTc of 500 milliseconds or greater compared with patients without COVID-19 (34 of 136 [25.0%] vs 17 of 158 [10.8%], P = .002). Multivariable analysis revealed that age 80 years and older compared with those younger than 50 years (mean difference in QTc, 11.91 [SE, 4.69; 95% CI, 2.73 to 21.09]; P = .01), severe chronic kidney disease compared with no chronic kidney disease (mean difference in QTc, 12.20 [SE, 5.26; 95% CI, 1.89 to 22.51; P = .02]), elevated high-sensitivity troponin levels (mean difference in QTc, 5.05 [SE, 1.19; 95% CI, 2.72 to 7.38]; P < .001), and elevated lactate dehydrogenase levels (mean difference in QTc, 5.31 [SE, 2.68; 95% CI, 0.06 to 10.57]; P = .04) were associated with QTc prolongation. Torsades de pointes occurred in 1 patient (0.1%) with COVID-19. Conclusions and Relevance: In this cohort study, COVID-19 infection was independently associated with significant mean QTc prolongation at days 5 and 2 of hospitalization compared with day 0. More patients with COVID-19 had QTc of 500 milliseconds or greater compared with patients without COVID-19.

Real-time stroke volume measurements for the optimization of cardiac resynchronization therapy parameters.

AIMS: We investigated the utility of real-time stroke volume (SV) monitoring via the arterial pulse power technique to optimize cardiac resynchronization therapy (CRT) parameters at implant and prospectively evaluated the clinical and echocardiographic results. METHODS AND RESULTS: Fifteen patients with ischaemic or non-ischaemic dilated cardiomyopathy, sinus rhythm, Class III congestive heart failure, and QRS >150 ms underwent baseline 2D echocardiogram (echo), 6 min walk distance, and quality of life (QOL) questionnaire within 1 week of implant. Following implant, 0.3 mmol lithium chloride was injected to calibrate SV via dilution curve. Atrioventricular (AV) delay (90, 120, 200 ms, baseline: atrial pacing only) and V-V delay (-80 to 80 ms in 20 ms increments) were varied every 60 s. The radial artery pulse power autocorrelation method (PulseCO algorithm, LiDCO, Ltd.) was used to monitor SV on a beat-to-beat basis (LiDCO, Ltd.). Optimal parameters were programmed and echo, 6 min walk, and QOL were repeated at 6-8 weeks post-implant. Nine patients had >5% increase in SV after optimization (Group A). Six patients had <5% improvement in SV (Group B). Compared with Group B, Group A had significant improvements in left ventricular ejection fraction (LVEF) (11.0 +/- 8.5 vs. 0.8 +/- 2.0%) and decrease in left ventricular end-diastolic dimension (LVEDD) (-0.6 +/- 0.4 vs. -0.2 +/- 0.2 cm) and 6 min walk (346 +/- 226 vs. 32 +/-271 ft, P < or = 0.05). Group A patients also tended to have greater improvement in the septal-to-posterior wall motion delay on M-mode echo (P = 0.07). CONCLUSION: Real-time SV measurements can be used to optimize CRT at the time of implant. Improvement in SV correlates with improvement in LVEF, LVEDD, and 6 min walk, and improvement in echocardiographic dyssynchrony.

Prognostic significance of QRS fragmentation and correlation with infarct size in patients with anterior ST-segment elevation myocardial infarction treated with percutaneous coronary intervention: Insights from the INFUSE-AMI trial.

BACKGROUND: QRS fragmentation (fQRS) is believed to reflect myocardial scar formation in patients with coronary disease. Whether early formation of fQRS in patients with ST-segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention (PCI) is correlated with infarct size and prognosis is unknown. We assessed the prognostic value of fQRS at 60min post-PCI and its correlation with infarct size in patients with anterior STEMI managed with primary PCI. METHODS: The INFUSE-AMI trial enrolled 452 patients with anterior STEMI undergoing primary PCI. Electrocardiograms (ECGs) were performed at baseline and 60min post-PCI. Infarct size was evaluated using cardiac magnetic resonance imaging at 30days post-PCI. Target vessel failure (TVF) was defined as the composite of cardiac death, target vessel myocardial infarction, or ischemia-driven target vessel revascularization. Study groups were defined as patients with versus without fQRS at 60min post-PCI. RESULTS: Out of 421 patients with ECG data 60min post-PCI, 68 patients (16.2%) had fQRS. Patients with versus without fQRS had similar baseline characteristics and infarct size (16.9%±8.7% vs. 16.1%±10.5%, p=0.62), but patients with fQRS had higher adjusted risk of 1-year TVF (adjusted HR 2.27, 95% CI 1.06-4.89, p=0.036) and a trend toward a higher risk of the composite cardiac death or target vessel myocardial infarction (9.0% vs. 4.1%, p=0.08) at 1year. CONCLUSION: fQRS in patients with STEMI is associated with TVF but does not correlate with infarct size.

Incidence, Predictors, and Outcomes of High-Grade Atrioventricular Block in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention (from the HORIZONS-AMI Trial).

High-grade atrioventricular block (HAVB) is historically considered a marker of worse outcomes in patients with ST-segment elevation myocardial infarction (STEMI). However, the predictors and prognostic impact of HAVB in the primary percutaneous coronary intervention (PCI) era remain poorly understood. We sought to describe the characteristics and predictors of HAVB in patients undergoing primary PCI in STEMI and to assess the prognostic significance of HAVB in the contemporary reperfusion era. The present analysis includes 3,115 patients presenting with STEMI from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial who underwent primary PCI. Outcomes were examined according to the presence of HAVB on a presenting electrocardiogram, as interpreted by an independent electrocardiography core laboratory. HAVB (second-degree Mobitz II or third-degree atrioventricular block) was present at baseline in 46 patients (1.5%). Independent predictors of HAVB included increased age, diabetes mellitus, right coronary artery occlusion, sum of ST-segment deviation, and baseline Thrombolysis In Myocardial Infarction flow 0/1. Thrombolysis In Myocardial Infarction flow 3 was restored in 83.7% and 91.5% of patients with versus without baseline HAVB respectively (p = 0.06). Mortality rate was significantly higher in patients with versus without HAVB at 30-day, 1-, and 3-year follow-ups (unadjusted hazard ratio [HR] 3.83, 95% CI 1.40 to 10.48; unadjusted HR 4.37, 95% CI 2.09 to 9.38 and unadjusted HR 2.78, 95% CI 1.31 to 5.91, respectively). After covariate adjustment, mortality rate was significantly higher in patients with HAVB at 1 year (adjusted HR 2.45, 95% CI 1.09 to 5.50, p = 0.03) but not at 30 days (adjusted HR 1.70, 95% CI 0.58 to 5.01, p = 0.33) or 3 years (adjusted HR 0.71 to 3.41, p = 0.27). In conclusion, HAVB is a rare complication of STEMI but remains associated with increased mortality, even after primary PCI.

Early Ventricular Tachycardia or Fibrillation in Patients With ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention and Impact on Mortality and Stent Thrombosis (from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction Trial).

The prevalence and impact of early ventricular arrhythmias (ventricular tachycardia [VT]/ventricular fibrillation [VF]) occurring before mechanical revascularization for acute ST segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention are poorly understood. We sought to investigate the association between early VT/VF and long-term clinical outcomes using data from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial. Among 3,602 patients with STEMI, 108 patients (3.0%) had early VT/VF. Baseline clinical characteristics were similar in patients with versus without early VT/VF. Patients with early VT/VF had shorter symptom-to-balloon times and lower left ventricular ejection fraction and underwent more frequent thrombectomy compared with patients without early VT/VF. Adjusted 3-year rates of all-cause death (15.7% vs 6.5%; adjusted hazard ratio 2.62, 95% confidence interval 1.48 to 4.61, p <0.001) and stent thrombosis (13.7% vs 5.7%; adjusted hazard ratio 2.74, 95% confidence interval 1.52 to 4.93, p <0.001) were significantly higher in patients with early VT/VF compared with patients without early VT/VF. In conclusion, in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial, VT/VF occurring before coronary angiography and revascularization in patients with STEMI was strongly associated with increased 3-year rates of death and stent thrombosis. Further investigation into the mechanisms underlying the increased risk of early stent thrombosis in patients with early VT/VF is required.

Prognostic implications of Q waves at presentation in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: An analysis of the HORIZONS-AMI study.

BACKGROUND: Presence of Q waves on the presenting electrocardiogram (ECG) in patients with ST-segment elevation myocardial infarction (STEMI) has been associated with worse prognosis; however, whether the prognostic value of Q waves is influenced by baseline characteristics and/or rapidity of revascularization based on the guideline-based metric of door-to-balloon time remains unknown. HYPOTHESIS: We hypothesized that Q waves in the presenting ECG will be predictive of long term mortality regardless of time to reperfusion. METHODS: The Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial enrolled 3602 patients with STEMI undergoing primary percutaneous coronary intervention. We stratified patients without prior history of myocardial infarction or coronary revascularization according to presence or absence of pathological Q waves on their presenting ECG. Associations between Q waves, death, and cardiovascular outcomes within 3 years were assessed using Cox proportional hazards regression. RESULTS: Among 2723 patients with evaluable ECGs, 1084 (39.8%) had Q waves on their presenting ECG. Male sex and time from symptom onset to balloon inflation were independent predictors of presence of Q waves. Patients with Q waves had higher adjusted risks of all-cause death (adjusted hazard ratio: 1.45, 95% confidence interval: 1.02-2.05, P = 0.04) and cardiac death (adjusted hazard ratio: 1.72, 95% confidence interval: 1.08-2.72, P = 0.02). The association between Q waves and cardiac death was consistent regardless of sex, diabetes status, target vessel, or door-to-balloon time (Pinteraction > 0.4 for all). CONCLUSIONS: Presence of Q waves on the presenting ECG in patients undergoing primary percutaneous coronary intervention due to STEMI is an independent predictor of mortality and adds prognostic value, regardless of sex or rapidity of revascularization.