Admission Cardiac Diagnostic Testing with Electrocardiography and Troponin Measurement Prognosticates Increased 30-Day Mortality in COVID-19.

Background Cardiovascular involvement in coronavirus disease 2019 (COVID-19) is common and leads to worsened mortality. Diagnostic cardiovascular studies may be helpful for resource appropriation and identifying patients at increased risk for death. Methods and Results We analyzed 887 patients (aged 64±17 years) admitted with COVID-19 from March 1 to April 3, 2020 in New York City with 12 lead electrocardiography within 2 days of diagnosis. Demographics, comorbidities, and laboratory testing, including high sensitivity cardiac troponin T (hs-cTnT), were abstracted. At 30 days follow-up, 556 patients (63%) were living without requiring mechanical ventilation, 123 (14%) were living and required mechanical ventilation, and 203 (23%) had expired. Electrocardiography findings included atrial fibrillation or atrial flutter (AF/AFL) in 46 (5%) and ST-T wave changes in 306 (38%). 27 (59%) patients with AF/AFL expired as compared to 181 (21%) of 841 with other non-life-threatening rhythms (P<0.001). Multivariable analysis incorporating age, comorbidities, AF/AFL, QRS abnormalities, and ST-T wave changes, and initial hs-cTnT ≥20 ng/L showed that increased age (HR 1.04/year), elevated hs-cTnT (HR 4.57), AF/AFL (HR 2.07), and a history of coronary artery disease (HR 1.56) and active cancer (HR 1.87) were associated with increased mortality. Conclusions Myocardial injury with hs-cTnT ≥20 ng/L, in addition to cardiac conduction perturbations, especially AF/AFL, upon hospital admission for COVID-19 infection is associated with markedly increased risk for mortality than either diagnostic abnormality alone.

Revisiting Atrial Fibrillation in the Transcatheter Aortic Valve Replacement Era.

Atrial fibrillation (AF) is a known complication of many cardiac procedures, including those undergoing surgical aortic valve replacement (SAVR). In the transcatheter aortic valve replacement (TAVR) era, AF has been noted not only to be present in these patients but also associated with morbidity and mortality. In this article, we first outline the significance of AF in general and then more specifically in patients undergoing cardiac surgery. We then compare and contrast specific clinical issues related to AF in patients with aortic stenosis undergoing aortic valve replacement, traditionally with SAVR, but now increasingly more common with TAVR.

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.

Bicuspid aortic valve increases risk of permanent pacemaker implant following aortic root replacement.

OBJECTIVES: We aimed to assess the incidence and possible differences in postoperative conduction delay after aortic root replacement (ARR) in bicuspid aortic valve (BAV) patients compared with a tricuspid aortic valve (TAV). METHODS: A total of 380 patients undergoing ARR at our institution between 2005 and 2013 were included in the analysis. Patients were stratified by aortic valve anatomy: BAV, n = 191 vs TAV, n = 189. Electrocardiographic and echocardiographic data were retrospectively analysed at different time points (pre-, postoperatively and at follow-up). Primary outcome of interest was permanent pacemaker (PPM) implantation within 30 days, the composite of new PPM or new left fascicular or bundle branch block (PPM or LBBB) was the secondary outcome of interest. Age range was 24-89.5 years and incidence of preoperative moderate to severe aortic stenosis was 9.7%. RESULTS: BAV patients had higher incidence of PPM implantation within 30 days (5.8 vs 1.6% in TAV, P = 0.053); moreover, the composite of PPM or LBBB was also more frequent in BAV (8.4 vs 2.1%, P = 0.010). BAV was independently associated with PPM insertion (OR 4.08, P = 0.047) and also an independent predictor of PPM or LBBB in multiple regression (OR 4.96, P = 0.006). CONCLUSIONS: Significantly higher incidence of PPM implantation or LBBB may exist after ARR in bicuspid patients and BAV was confirmed to be an independent predictor for postoperative conduction disturbances by multivariable regression.

Effect of Ischemia Duration and Door-to-Balloon Time on Myocardial Perfusion in ST-Segment Elevation Myocardial Infarction: An Analysis From HORIZONS-AMI Trial (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction).

OBJECTIVES: This study sought to investigate the effect of treatment delay on microvascular reperfusion in ST-segment elevation myocardial infarction (STEMI) patients from the large, multicenter, prospective HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial. BACKGROUND: Despite restoration of epicardial blood flow during primary percutaneous coronary intervention (PCI), one-third of patients do not obtain myocardial perfusion due to impairment in the microvascular circulation. METHODS: We examined the effect of symptom onset-to-balloon time (SBT) and door-to-balloon time (DBT) on myocardial reperfusion during primary PCI in STEMI, utilizing resolution of ST-segment elevation (STR) and the myocardial blush grade (MBG). The primary analysis was the relationships between SBT ≤2, >2 to 4, and >4 h and DBT ≤1, >1 to 1.5, >1.5 to 2, and >2 h with MBG and STR. Clinical risk was assessed using a modified version of the Thrombolysis In Myocardial Infarction risk score for STEMI. RESULTS: In 2,056 patients, absent microvascular perfusion (MBG 0/1) and STR (STR <30%) after primary PCI was significantly more common in patients with longer SBT, in patients with both low and high clinical risk profiles. By multivariable analysis, SBT (p < 0.0001), anterior infarction (p < 0.0001), reference vessel diameter (p = 0.005), lesion minimum lumen diameter (p < 0.0001), hyperlipidemia (p = 0.03), and current smoking (p = 0.001) were independent predictors of MBG 0/1, whereas SBT (p = 0.007), anterior infarction (p < 0.0001), and history of renal insufficiency (p = 0.0002) were independent predictors of absent STR. DBT (p < 0.0001) was an independent predictor of MBG 0/1. MBG 0/1 and STR<30% identified patients with increased 3-year mortality. CONCLUSIONS: The present study suggests that delay in mechanical reperfusion therapy during STEMI is associated with greater injury to the microcirculation.

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.

Relation of QRS shortening to cardiac output during temporary resynchronization therapy after cardiac surgery.

Cardiac resynchronization therapy (CRT) can improve cardiac function in heart failure without increasing myocardial oxygen consumption. However, CRT optimization based on hemodynamics or echocardiography is difficult. QRS duration (QRSd) is a possible alternative optimization parameter. Accordingly, we assessed QRSd optimization of CRT during cardiac surgery. We hypothesized that QRSd shortening during changes in interventricular pacing delay (VVD) would increase cardiac output (CO). Seven patients undergoing coronary artery bypass, aortic or mitral valve surgery with left ventricular (LV) ejection fraction < or =40%, and QRSd > or =100 msec were studied. CRT was implemented at epicardial pacing sites in the left and right ventricle and right atrium during VVD variation after cardiopulmonary bypass. QRSd was correlated with CO from an electromagnetic aortic flow probe. Both positive and negative correlations were observed. Correlation coefficients ranged from 0.70 to -0.74 during VVD testing. Clear minima in QRSd were observed in four patients and were within 40 msec of maximum CO in two. We conclude that QRSd is not useful for routine optimization of VVD after cardiac surgery but may be useful in selected patients. Decreasing QRSd is associated with decreasing CO in some patients, suggesting that CRT can affect determinants of QRSd and ventricular function independently.

Atrial flutter catheter ablation in adult patients with repaired tetralogy of Fallot: mechanisms and outcomes of percutaneous catheter ablation in a consecutive series.

BACKGROUND: Prior investigators note successful ablation of both typical cavotricuspid isthmus-dependent and scar-related macroreentrant right atrial flutters (AFL) in adult patients with repaired tetralogy of Fallot (TOF). However, an analysis of the mechanisms (including a description of a uniform approach to diagnose such mechanisms), and clinical outcomes of catheter ablation in a consecutive series of adult patients with AFL late after surgical TOF repair has not been previously reported. METHODS: Background clinical data and follow-up were evaluated in a consecutive series of TOF patients evaluated from September 2001 to June 2008. RESULTS: We report a prevalence of sustained, symptomatic AFL in patients with repaired TOF equal to 20% (28/140 patients), and of recurrent, drug-refractory and/or severely symptomatic AFL to be 11% (16/140 patients). The AFLs manifested variable cycle lengths ranging from 215 to 525 ms. Underlying mechanisms were: (1) cavotricuspid (CTI)-dependent, counterclockwise atrial flutter (n=8 patients); (2) non-CTI-dependent macroreentrant scar-related AFL (n=6 patients); and (3) both CTI- and non-CTI-dependent macroreentrant AFL (n=2 patients). Recurrent arrhythmias occurred in six patients, five of whom were successfully treated with repeat ablation. After a mean follow-up of 23 months, 15 of 16 patients were alive and free of sustained AFL. CONCLUSIONS: AFL late after surgical TOF repair occurs in 20% of such patients. In more than half of these patients, the AFLs are drug-refractory and/or severely symptomatic. Despite the presence of congenital heart disease treated with prior cardiac surgery and AFLs with variable atrial cycle lengths, the CTI-dependent mechanism underlies approximately half of the sustained, symptomatic AFLs.

A comparison of atrial arrhythmias after heart or double-lung transplantation at a single center: insights into the mechanism of post-operative atrial fibrillation.

OBJECTIVES: We compared the incidence of atrial arrhythmias in double-lung transplant patients versus heart transplant patients to gain insight into factors that contribute to post-operative atrial fibrillation (AF). BACKGROUND: Atrial fibrillation is a common complication after thoracic surgery. Pulmonary vein isolation is an effective treatment for AF. Heart or double-lung transplantation surgery both involve pulmonary vein isolation because of suture lines. METHODS: We reviewed the records of 174 consecutive heart transplant patients and 122 double-lung transplant patients at the Columbia Presbyterian Medical Center between January 2005 and June 2008. Electrocardiograms during atrial arrhythmia episodes were reviewed by an electrophysiologist. Clinical variables, biopsy results, immunosuppressive regimens, and echocardiographic measurements were collected from the perioperative time period and at the time of arrhythmia occurrence. RESULTS: In the heart transplant group, 8 (4.6%) patients had AF (group A). In the lung transplant group, 23 (18.9%) patients had AF (group B; p < 0.001). The incidence of AF in a comparison group of 131 patients with normal left ventricular function who underwent coronary artery bypass graft surgery was 19.8%. Immunosuppressive regimens and clinical variables were similar for both groups. Echocardiographic data revealed no significant cardiac abnormalities in 74% of group B compared with 25% of group A (p < 0.05), and 78% of biopsy results in group B were normal, whereas only 25% of group A results were normal (p < 0.05). CONCLUSIONS: In heart transplant recipients, AF is uncommon and occurs in the setting of myocardial dysfunction and graft rejection. In contrast, AF is more common after lung transplantation despite the absence of graft rejection and cardiac dysfunction. Pulmonary vein isolation alone cannot explain the discrepancy in AF incidence between heart transplant recipients and double-lung transplant recipients. Cardiac autonomic denervation may have a protective effect for heart transplant patients in the post-operative setting.

Unexpected, dramatic improvement in atrioventricular conduction during pacemaker implantation for apparent complete heart block.

We describe the case of a 29-year-old man with complete heart block after aortic and mitral valve surgery for bacterial endocarditis. Prior to pacemaker implantation, the patient had sinus bradycardia with third degree atrioventricular (AV) block. During testing of the atrial lead, the patient manifested intact AV conduction with a constant PR interval, which was robust up to 120 beats/min. This case represents a dramatic example of unexpected, improved AV conduction, perhaps a result of loss of Phase IV block.

Effect of acute cocaine administration on the QTc interval of habitual users.

The proarrhythmic effects of cocaine may be mediated in part by its effects on cardiac repolarization properties. This study evaluated the acute effects of smoking cocaine 25 mg on the electrocardiograms of 14 habitual cocaine users during a 12-minute observation period. After cocaine administration, heart rate increased by a mean of 22 beats/min (p <0.0001). One patient developed accelerated junctional rhythm, and 5 had nonspecific ST-T-wave abnormalities. The electrocardiograms revealed significant prolongation of the QTc interval (p <0.001) after cocaine administration. In addition, T-wave amplitude decreased and U-wave amplitude increased in response to cocaine use (p <0.05). QRS duration was unchanged by cocaine, whereas the PR interval shortened slightly. The repolarization changes observed after cocaine use were similar to those reported for other sympathomimetic agents and may be a contributing factor in the association between cocaine use and ventricular arrhythmias.