Benefit of isolated surgical valve repair or replacement for functional tricuspid regurgitation and long-term outcomes stratified by the TRI-SCORE.

BACKGROUND AND AIMS: Severe tricuspid regurgitation (TR) is associated with increased mortality rates, but benefit of its correction and ideal timing are not clearly determined. This study aimed to identify patient subsets who might benefit from surgery. METHODS: In TRIGISTRY, an international cohort study of consecutive patients with severe isolated functional TR (33 centers, 10 countries), survival rates up to 10 years were compared between patients who underwent isolated tricuspid valve (TV) surgery (repair or replacement) and those conservatively managed, overall and according to TRI-SCORE category (low: ≤3, intermediate: 4-5, high: ≥6). RESULTS: 1,217 were managed conservatively, and 551 underwent isolated TV surgery (200 repairs, 351 replacements). TRI-SCORE distribution was 33% low, 32% intermediate, and 35% high. At 10 years, survival rates were similar between surgical and conservative management (41% vs. 36%; hazard ratio [HR] 0.97; 95% confidence interval [CI] 0.88-1.08, P=0.57). Surgery improved survival compared to conservative management in the low TRI-SCORE category (72% vs. 44%; HR 0.27; 95% CI 0.20-0.37, P<0.0001), but not in the intermediate (36% vs. 37%, HR 1.17; 95%CI 0.98-1.40, P=0.09) or high categories (20% vs. 24%; HR 1.06; 95% CI 0.91-1.25, P=0.45). Both repair and replacement improved survival in the low TRI-SCORE category (84% and 61% vs. 44%; HR 0.11; 95% CI 0.06-0.19, P<0.0001, and HR 0.65; 95% CI 0.47-0.90, P=0.009). Repair showed benefit in the intermediate category (59% vs. 37%; HR 0.49; 95% CI 0.35-0.68, P<0.0001) while replacement was possibly harmful (25% vs. 37%; HR 1.43; 95% CI 1.18-1.72, P=0.0002). CONCLUSIONS: Higher survival rates were observed with repair than replacement and benefit of intervention declined as TRI-SCORE increased with no benefit of any type of surgery in the high TRI-SCORE category. These results emphasize the importance of timely intervention and patient selection to achieve the best outcomes and the need for randomized controlled trials. TRIAL REGISTRATION: TRIGISTRY: ClinicalTrials.gov, NCT05825898.

Milrinone as Compared with Dobutamine in the Treatment of Cardiogenic Shock.

BACKGROUND: Cardiogenic shock is associated with substantial morbidity and mortality. Although inotropic support is a mainstay of medical therapy for cardiogenic shock, little evidence exists to guide the selection of inotropic agents in clinical practice. METHODS: We randomly assigned patients with cardiogenic shock to receive milrinone or dobutamine in a double-blind fashion. The primary outcome was a composite of in-hospital death from any cause, resuscitated cardiac arrest, receipt of a cardiac transplant or mechanical circulatory support, nonfatal myocardial infarction, transient ischemic attack or stroke diagnosed by a neurologist, or initiation of renal replacement therapy. Secondary outcomes included the individual components of the primary composite outcome. RESULTS: A total of 192 participants (96 in each group) were enrolled. The treatment groups did not differ significantly with respect to the primary outcome; a primary outcome event occurred in 47 participants (49%) in the milrinone group and in 52 participants (54%) in the dobutamine group (relative risk, 0.90; 95% confidence interval [CI], 0.69 to 1.19; P = 0.47). There were also no significant differences between the groups with respect to secondary outcomes, including in-hospital death (37% and 43% of the participants, respectively; relative risk, 0.85; 95% CI, 0.60 to 1.21), resuscitated cardiac arrest (7% and 9%; hazard ratio, 0.78; 95% CI, 0.29 to 2.07), receipt of mechanical circulatory support (12% and 15%; hazard ratio, 0.78; 95% CI, 0.36 to 1.71), or initiation of renal replacement therapy (22% and 17%; hazard ratio, 1.39; 95% CI, 0.73 to 2.67). CONCLUSIONS: In patients with cardiogenic shock, no significant difference between milrinone and dobutamine was found with respect to the primary composite outcome or important secondary outcomes. (Funded by the Innovation Fund of the Alternative Funding Plan for the Academic Health Sciences Centres of Ontario; ClinicalTrials.gov number, NCT03207165.).

High-power short-duration versus low-power long-duration ablation for pulmonary vein isolation: A substudy of the AWARE randomized controlled trial.

INTRODUCTION: Pulmonary vein isolations (PVI) are being performed using a high-power, short-duration (HPSD) strategy. The purpose of this study was to compare the clinical efficacy and safety outcomes of an HPSD versus low-power, long-duration (LPLD) approach to PVI in patients with paroxysmal atrial fibrillation (AF). METHODS: Patients were grouped according to a HPSD (≥40 W) or LPLD (≤35 W) strategy. The primary endpoint was the 1-year recurrence of any atrial arrhythmia lasting ≥30 s, detected using three 14-day ambulatory continuous ECG monitoring. Procedural and safety endpoints were also evaluated. The primary analysis were regression models incorporating propensity scores yielding adjusted relative risk (RRa ) and mean difference (MDa ) estimates. RESULTS: Of the 398 patients included in the AWARE Trial, 173 (43%) underwent HPSD and 225 (57%) LPLD ablation. The distribution of power was 50 W in 75%, 45 W in 20%, and 40 W in 5% in the HPSD group, and 35 W with 25 W on the posterior wall in the LPLD group. The primary outcome was not statistically significant at 30.1% versus 22.2% in HPSD and LPLD groups with RRa 0.77 (95% confidence interval [CI]) 0.55-1.10; p = .165). The secondary outcome of repeat catheter ablation was not statistically significant at 6.9% and 9.8% (RRa 1.59 [95% CI 0.77-3.30]; p = .208) respectively, nor was the incidence of any ECG documented AF during the blanking period: 1.7% versus 8.0% (RRa 3.95 [95% CI 1.00-15.61; p = .049) in the HPSD versus LPLD group respectively. The total procedure time was significantly shorter in the HPSD group (MDa 97.5 min [95% CI 84.8-110.4)]; p < .0001) with no difference in adjudicated serious adverse events. CONCLUSIONS: An HPSD strategy was associated with significantly shorter procedural times with similar efficacy in terms of clinical arrhythmia recurrence. Importantly, there was no signal for increased harm with a HPSD strategy.

Transcatheter mitral valve repair for inotrope dependent cardiogenic shock - Design and rationale of the CAPITAL MINOS trial.

BACKGROUND: Functional mitral regurgitation (MR) is an important clinical consideration in patients with heart failure. Transcatheter edge-to-edge repair (TEER) has emerged as a useful therapeutic tool for patients with chronic heart failure, however the role of TEER in patients with cardiogenic shock (CS) and MR has not yet been studied in a randomized trial. The Transcatheter Mitral Valve Repair for Inotrope Dependent Cardiogenic Shock (CAPITAL MINOS) trial was therefore designed to determine if TEER improves clinical outcomes in the CS population. METHODS AND DESIGN: The CAPITAL MINOS trial is an open-label, multi-center randomized clinical trial comparing TEER to medical therapy in patients with CS and MR. A total of 144 patients with Society for Cardiovascular Angiography and Interventions (SCAI) class C or D CS and at least 3+ MR will be randomized in a 1:1 ratio to TEER or medical therapy alone. The primary outcome will be a composite of in-hospital all-cause mortality, cardiac transplantation, implantation of durable left ventricular assist device, or discharge on palliative inotropic therapy. Patients will be followed for the duration of their index hospitalization for the primary outcome. Secondary outcomes include 6 month mortality. IMPLICATIONS: The CAPITAL MINOS trial will determine whether TEER improves outcomes in patients with CS and MR and will be an important step in optimizing treatment for this high-risk patient population.

Metabolic activity of the left and right atria are differentially altered in patients with atrial fibrillation and LV dysfunction.

BACKGROUND: Alterations in atrial metabolism may play a role in the perpetuation of atrial fibrillation (AF). This study sought to compare 18F-fluorodeoxyglucose (FDG) uptake on PET, in patients with LV dysfunction versus those without AF. METHODS: Seventy-two patients who underwent myocardial viability assessment were evaluated. AF patients (36) had persistent or permanent AF based on history and ECG. Patients without AF (36) were matched to AF patients based on sex, diabetes, age, and LVEF. Maximum and mean FDG Standard Uptake Values (SUV) in the left atrial (LA) wall and right atrial (RA) wall were measured. Tissue-to-blood ratios (TBR) were calculated as atrial wall to blood-pool activity. Atrial volumes were measured by echocardiography. RESULTS: Maximum and mean FDG SUV and TBRs were significantly increased in the RA (but not the LA) of patients with AF compared to those without (P < 0.01). When accounting for changes in atrial volume, the presence of AF remained a significant predictor of higher RAMAX, but not RAMEAN FDG uptake. CONCLUSION: In patients with LV dysfunction from ischemic cardiomyopathy, LA and RA glucose metabolism are differentially altered in those with persistent atrial fibrillation. Further investigations should elucidate the temporal relationship between AF and glucose metabolic changes, as a potential target for therapy.

Acute kidney injury after radial or femoral artery access in ST-segment elevation myocardial infarction: AKI-SAFARI.

BACKGROUND: Acute kidney injury (AKI) complicating primary percutaneous coronary intervention (PCI) is an independent predictor of short- and long-term outcomes in patients presenting with ST-elevation myocardial infarction (STEMI). Prior studies suggest a lower incidence of AKI in patients undergoing PCI through radial artery compared to femoral artery access; however, no randomized clinical trials have specifically investigated this question in patients presenting with STEMI. METHODS: To determine whether radial access (RA) is associated with a reduced frequency of AKI following primary PCI, we performed a substudy of the SAFARI-STEMI trial. The SAFARI-STEMI trial was an open-label, multicenter trial, which randomized patients presenting with STEMI to RA or femoral access (FA), between July 2011 and December 2018. The primary outcome of this post hoc analysis was the incidence of AKI, defined as an absolute (>0.5 mg/dL) or relative (>25%) increase in serum creatinine from baseline. RESULTS: In total 2,285 (99.3%) of the patients enrolled in SAFARI-STEMI were included in the analysis-1,132 RA and 1,153 FA. AKI occurred in 243 (21.5%) RA patients and 226 (19.6%) FA patients (RR: 0.91, 95% CI: 0.78-1.07, P = .27). An absolute increase in serum creatinine >0.5 mg/dL was seen in 49 (4.3%) radial and 52 (4.5%) femoral patients (RR: 1.04, 95% CI: 0.71-1.53, P = .83). AKI was lower in both groups when the KDIGO definition was applied (RA 11.9% vs FA 10.8%; RR: 0.90, 95% CI: 0.72-1.13, P = .38). CONCLUSIONS: Among STEMI patients enrolled in the SAFARI-STEMI trial, there was no association between catheterization access site and AKI, irrespective of the definition applied. These results challenge the independent association between catheterization access site and AKI noted in prior investigations.

Validation of multiparametric rubidium-82 PET myocardial blood flow quantification for cardiac allograft vasculopathy surveillance.

BACKGROUND: We previously demonstrated high diagnostic accuracy of Rubidium-82 positron emission tomography (PET) myocardial blood flow (MBF) quantification for CAV. The purpose of this study was to validate multiparametric PET detection of CAV by combined rate-pressure-product-corrected myocardial flow reserve (cMFR), stress MBF, and coronary vascular resistance (CVR) assessment. METHODS AND RESULTS: Diagnostic CAV cut-offs of cMFR < 2.9, stress MBF < 2.3, CVR > 55 determined in a previous study (derivation) were assessed in heart transplant recipients referred for coronary angiography and intravascular ultrasound (IVUS) (validation). CAV was defined as International Society of Heart and Lung Transplantation CAV1-3 on angiography; and maximal intimal thickness ≥ 0.5 mm on IVUS. Eighty patients (derivation n = 40, validation n = 40) were included: 80% male, mean age 54±14 years, 4.5±5.6 years post transplant. The prevalence of CAV was 44% on angiography and 78% on IVUS. Combined PET cMFR < 2.9, stress MBF < 2.3, CVR > 55 CAV assessment yielded high 88% (specificity 75%) and 83% (specificity 40%) sensitivity for ≥ 1 abnormal parameter and high 88% (sensitivity 59%) and 90% (sensitivity 43%) specificity for 3 abnormal parameters, in the derivation and validation cohorts, respectively. CONCLUSION: We validate the diagnostic accuracy of multiparametric PET flow quantification by cMFR, stress MBF, and CVR for CAV.

Impact of baseline beta-blocker use on inotrope response and clinical outcomes in cardiogenic shock: a subgroup analysis of the DOREMI trial.

BACKGROUND: Cardiogenic shock (CS) is associated with significant morbidity and mortality. The impact of beta-blocker (BB) use on patients who develop CS remains unknown. We sought to evaluate the clinical outcomes and hemodynamic response profiles in patients treated with BB in the 24 h prior to the development of CS. METHODS: Patients with CS enrolled in the DObutamine compaREd to MIlrinone trial were analyzed. The primary outcome was a composite of all-cause mortality, resuscitated cardiac arrest, need for cardiac transplant or mechanical circulatory support, non-fatal myocardial infarction, transient ischemic attack or stroke, or initiation of renal replacement therapy. Secondary outcomes included the individual components of the primary composite and hemodynamic response profiles derived from pulmonary artery catheters. RESULTS: Among 192 participants, 93 patients (48%) had received BB therapy. The primary outcome occurred in 47 patients (51%) in the BB group and in 52 (53%) in the no BB group (RR 0.96; 95% CI 0.73-1.27; P = 0.78) throughout the in-hospital period. There were fewer early deaths in the BB group (RR 0.41; 95% CI 0.18-0.95; P = 0.03). There were no differences in other individual components of the primary outcome or in hemodynamic response between the two groups throughout the remainder of the hospitalization. CONCLUSIONS: BB therapy in the 24 h preceding the development of CS did not negatively influence clinical outcomes or hemodynamic parameters. On the contrary, BB use was associated with fewer deaths in the early resuscitation period, suggesting a paradoxically protective effect in patients with CS. Trial registration ClinicalTrials.gov Identifier: NCT03207165.

The role of brain natriuretic peptide in atrial fibrillation: a substudy of the Substrate Modification with Aggressive Blood Pressure Control for Atrial Fibrillation (SMAC-AF) trial.

BACKGROUND: Catheter ablation is an established therapy for atrial fibrillation but is limited by recurrence; efforts have been made to identify biomarkers that predict recurrence. We investigated the effect of baseline NT-proBNP on AF recurrence following catheter ablation in patients randomized to aggressive (< 120/80 mmHg) or standard blood pressure management (< 140/90 mmHg) in the Substrate Modification with Aggressive Blood Pressure Control trial (SMAC-AF). METHODS: The SMAC-AF study included 173 patients resistant or intolerant to at least one class I or III antiarrhythmic drug. We studied the effect of baseline NT-proBNP on the primary outcome of AF recurrence > 3 months post-ablation. RESULTS: Of the 173 patients, 88 were randomized to the aggressive cohort, and 85 into the standard group. The primary outcome occurred in 61.4% of those in the aggressive arm, versus 61.2% in the standard arm. In the aggressive group, logNT-proBNP predicted recurrence (HR 1.28, p = 0.04, adjusted HR 1.43, p = 0.03), while in the standard cohort, it did not (HR 0.94, p = 0.62, adjusted HR 0.83, p = 0.22). NT-proBNP ≥ 280 pg/mL also predicted occurrence in the aggressive (HR 1.98, p = 0.02) but not the standard cohort (HR 1.00, p = 1.00). CONCLUSION: We conclude that pre-ablation NT-proBNP may be useful in predicting recurrence in hypertensive patients and identifying patients who benefit from aggressive blood control and upstream therapies. TRIAL REGISTRATION: NCT00438113, registered February 21, 2007.

Effect of Moderate vs Mild Therapeutic Hypothermia on Mortality and Neurologic Outcomes in Comatose Survivors of Out-of-Hospital Cardiac Arrest: The CAPITAL CHILL Randomized Clinical Trial.

Importance: Comatose survivors of out-of-hospital cardiac arrest experience high rates of death and severe neurologic injury. Current guidelines recommend targeted temperature management at 32 °C to 36 °C for 24 hours. However, small studies suggest a potential benefit of targeting lower body temperatures. Objective: To determine whether moderate hypothermia (31 °C), compared with mild hypothermia (34 °C), improves clinical outcomes in comatose survivors of out-of-hospital cardiac arrest. Design, Setting, and Participants: Single-center, double-blind, randomized, clinical superiority trial carried out in a tertiary cardiac care center in eastern Ontario, Canada. A total of 389 patients with out-of-hospital cardiac arrest were enrolled between August 4, 2013, and March 20, 2020, with final follow-up on October 15, 2020. Interventions: Patients were randomly assigned to temperature management with a target body temperature of 31 °C (n = 193) or 34 °C (n = 196) for a period of 24 hours. Main Outcomes and Measures: The primary outcome was all-cause mortality or poor neurologic outcome at 180 days. Neurologic outcome was assessed using the Disability Rating Scale, with poor neurologic outcome defined as a score greater than 5 (range, 0-29, with 29 being the worst outcome [vegetative state]). There were 19 secondary outcomes, including mortality at 180 days and length of stay in the intensive care unit. Results: Among 367 patients included in the primary analysis (mean age, 61 years; 69 women [19%]), 366 (99.7%) completed the trial. The primary outcome occurred in 89 of 184 patients (48.4%) in the 31 °C group and in 83 of 183 patients (45.4%) in the 34 °C group (risk difference, 3.0% [95% CI, 7.2%-13.2%]; relative risk, 1.07 [95% CI, 0.86-1.33]; P = .56). Of the 19 secondary outcomes, 18 were not statistically significant. Mortality at 180 days was 43.5% and 41.0% in patients treated with a target temperature of 31 °C and 34 °C, respectively (P = .63). The median length of stay in the intensive care unit was longer in the 31 °C group (10 vs 7 days; P = .004). Among adverse events in the 31 °C group vs the 34 °C group, deep vein thrombosis occurred in 11.4% vs 10.9% and thrombus in the inferior vena cava occurred in 3.8% and 7.7%, respectively. Conclusions and Relevance: In comatose survivors of out-of-hospital cardiac arrest, a target temperature of 31 °C did not significantly reduce the rate of death or poor neurologic outcome at 180 days compared with a target temperature of 34 °C. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT02011568.

In-hospital outcomes of STEMI patients on warfarin undergoing primary PCI.

OBJECTIVES: We sought to describe the safety and efficacy outcomes of patients on warfarin presenting with ST-elevation myocardial infarction (STEMI). BACKGROUND: Limited data exist on the outcomes and optimal management of STEMI patients on warfarin undergoing primary percutaneous coronary intervention (PCI). METHODS: Baseline characteristics and outcomes were prospectively collected for 2,390 consecutive STEMI patients referred for primary PCI. Patients were stratified based on warfarin use at baseline. The primary safety endpoint was the rate of in-hospital bleeding (a composite of major bleeding or minor bleeding) according to the thrombolysis in myocardial infarction (TIMI) classification. Efficacy endpoints included major adverse cardiovascular events (MACE), defined as death, myocardial infarction, or stroke, as well as intracranial bleeding, cardiogenic shock, and length of stay. Multiple logistic regression was used to determine if warfarin was independently associated with bleeding and MACE. RESULTS: Warfarin patients (n = 59 vs. n = 2,331) were significantly older (73.2 years vs. 61.7 years; P < 0.01), and more likely to present as Killip Class IV (13.6% vs. 2.7%; P < 0.01). TIMI major/minor bleeding occurred in 30.4% of the warfarin patients and 14.2% of the control patients (P < 0.01). After adjustment warfarin was independently associated with an increased risk of bleeding (OR 2.08; P = 0.04). Warfarin patients also had an increased frequency of MACE (20.3% vs. 5.9%; P < 0.01), though this was not significant after adjustment (OR 2.00; P = 0.10). CONCLUSIONS: STEMI patients on warfarin referred for primary PCI are more likely to experience bleeding. New strategies are needed to optimize the management and minimize bleeding in this high-risk population.

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial.

BACKGROUND: Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. METHODS: We compared the modified Allen test with a smartphone heart rate-monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient's index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate-monitoring application. RESULTS: Among 438 patients who were included in the study, we found that the heart rate-monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). INTERPRETATION: A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient's bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491.

Comparison of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) in corticosteroid-naive patients with conduction system disease due to cardiac sarcoidosis.

PURPOSE: Cardiac sarcoidosis (CS) is a cause of conduction system disease (CSD). (18)F-Fluorodeoxyglucose-positron emission tomography (FDG PET) and cardiac magnetic resonance (CMR) are used for detection of CS. The relative diagnostic value of these has not been well studied. The aim was to compare these imaging modalities in this population. METHODS: We recruited steroid-naive patients with newly diagnosed CSD due to CS. All CS patients underwent both imaging studies within 12 weeks of each other. Patients were classified into two groups: group A with chronic mild CSD (right bundle branch block and/or axis deviation), and group B with new-onset atrioventricular block (AVB, Mobitz type II or third-degree AVB). RESULTS: Thirty patients were included. Positive findings on both imaging studies were seen in 72 % of patients (13/18) in group A and in 58 % of patients (7/12) in group B. The remainder (28 %) of the patients in group A were positive only on CMR. Of the patients in group B, 8 % were positive only on CMR and 33 % were positive only on FDG PET. Patients in group A were more likely to be positive only on CMR, and patients in group B were more likely to be positive only on FDG PET (p = 0.02). Patients in group B positive only on FDG PET underwent CMR earlier relative to their symptomatology than patients positive only on CMR (median 7.0, IQR 1.5 - 34.3, vs. 72.0, IQR 25.0 - 79.5 days; p = 0.03). CONCLUSION: The number of positive FDG PET and CMR studies was different in patients with CSD depending on their clinical presentation. This study demonstrated that CMR can adequately detect cardiac involvement associated with chronic mild CSD. In patients presenting with new-onset AVB and a negative CMR study, FDG PET may be useful for detecting cardiac involvement due to CS.

A prospective placebo controlled randomized study of caffeine in patients with supraventricular tachycardia undergoing electrophysiologic testing.

INTRODUCTION: Patients with cardiac arrhythmias are generally instructed to avoid caffeine intake. A comprehensive evaluation of the electrophysiological effects of caffeine on atrial and ventricular tissues in humans has not previously been performed. METHODS AND RESULTS: Eighty patients (31 men, mean age 49 ± 14 years) with symptomatic supraventricular tachycardia (SVT) undergoing an electrophysiologic study (EPS) prior to catheter ablation were randomized to receive oral caffeine or placebo. Caffeine at a dosage of 5 mg/kg (moderate intake) or placebo tablets were administered orally at a mean time of 57 ± 13 minutes prior to the EPS. The median (IQR) caffeine level in patients receiving caffeine was 7.4 µg/mL (4.7-8.7), as compared with 0.15 (0.00-0.61) in patients receiving placebo, P < 0.0001. Caffeine was associated with a significant increase in resting systolic and diastolic blood pressures as compared with placebo, while the resting heart rate was not significantly different between both groups. Caffeine was not associated with significant effects on the effective refractory period of the atrium or ventricle, as well as on AV node conduction. SVT was induced in all but 3 patients; there was no significant difference between groups receiving placebo or caffeine on SVT inducibility or the cycle length of induced tachycardias. CONCLUSIONS: Caffeine, at moderate intake, was associated with significant increases in systolic and diastolic blood pressures, but had no evidence of a significant effect on cardiac conduction and refractoriness. Furthermore, no effect of caffeine on SVT induction or more rapid rates of induced tachycardias was found.

Contact force mapping and voltage thresholds during high-frequency stimulation of human cardiac ganglionated plexuses†.

AIMS: The intrinsic cardiac nervous system consists of ganglionated plexuses (GPs) localized epicardially to specific regions of the left atrium (LA). The relation between voltage thresholds and endocardial contact force associated with autonomic effects during stimulation of GPs has not previously been evaluated. METHODS AND RESULTS: Sixteen patients with symptomatic atrial fibrillation (AF) underwent mapping of GPs prior to radiofrequency ablation of AF. Pre-acquired computed tomographic images were merged with 3D non-fluoroscopic electroanatomic mapping of the LA. Using high-frequency stimulation (HFS), the voltage thresholds of GPs was obtained while patients received conscious sedation. At each location, the contact force measurement from the catheter was correlated with the voltage applied during HFS at 5, 10, or 15 V to obtain an autonomic effect, usually associated with asystole, or marked bradycardia. There were 192 applications of HFS, resulting in GP identification in all patients (mean 3.4 per patient, range 1-5). During HFS, an autonomic response was significantly more likely to occur at 10 V as compared with 5 V (P < 0.008). There was no significant relation between the measured contact force and the likelihood of obtaining an autonomic response. When performing HFS at 15 V, a sudden overshoot with maximal values of contact force of up to 100 g was also observed. High-frequency stimulation was well tolerated, without associated adverse events. CONCLUSION: An autonomic response during HFS was significantly more likely to occur at 10 V as compared with 5 V. Although the GPs are epicardial structures, significant contact force was not required for their localization.

Limitations of free-form-text diagnostic requisitions as a tool for evaluating adherence to appropriate use criteria for transthoracic echocardiography.

BACKGROUND: Monitoring the adherence to Appropriateness Use Criteria (AUC) has been identified as an important component for the accreditation of echocardiography laboratories. Referral requisitions are a logical tool to rapidly determine the appropriateness of transthoracic echocardiography (TTE) referrals, however data is lacking. We investigated whether standard free-form-text TTE referral requisitions can be used to evaluate AUC adherence. METHODS: Consecutive TTE referral requisitions to the University of Ottawa Heart Institute echocardiography laboratory were reviewed over a four-week period. Indication on the requisition was matched with the relevant indication on the 2011 American College of Cardiology Foundation (ACCF) AUC. Requisitions that did not provide sufficient information to identify the relevant AUC indication were identified as inadequate. For inadequate requisitions, reason for the referral was clarified through medical records and referring physicians. RESULTS: Of the 1303 requisitions, 26.2% did not provide adequate information to determine adherence to AUC, despite a non-adherence (inappropriate) rate of only 6.1% in the referral population. Indication for referral, physician specialty, outpatient status, and prior echocardiogram were independent predictors of inadequate requisitions (p < 0.001, respectively). The most common reasons for inadequate requisitions were a failure to report: 1) change in clinical status, 2) date of a prior echocardiogram, and 3) type and/or severity of a valve lesion. Inclusion of this information would have decreased the inadequacy rate by 56%. CONCLUSION: In a large, academic echocardiography laboratory, over one quarter of free-form-text TTE requisitions are inadequate to evaluate AUC adherence. Structured requisition formats requiring AUC-relevant information are needed to facilitate the practical application of AUC in the echocardiography laboratory.

Prognostic Implications of Residual Tricuspid Regurgitation Grading After Transcatheter Tricuspid Valve Repair.

BACKGROUND: The safety profile of transcatheter tricuspid valve (TTV) repair techniques is well established, but residual tricuspid regurgitation (TR) remains a concern. OBJECTIVES: The authors sought to assess the impact of residual TR severity post-TTV repair on survival. METHODS: We evaluated the survival rate at 2 years of 613 patients with severe isolated functional TR who underwent TTV repair in TRIGISTRY according to the severity of residual TR at discharge using a 3-grade (mild, moderate, and severe) or 4-grade scheme (mild, mild to moderate, moderate to severe, and severe). RESULTS: Residual TR was none/mild in 33%, moderate in 52%, and severe in 15%. The 2-year adjusted survival rates significantly differed between the 3 groups (85%, 70%, and 44%, respectively; restricted mean survival time [RMST]: P = 0.0001). When the 319 patients with moderate residual TR were subdivided into mild to moderate (n = 201, 33%) and moderate to severe (n = 118, 19%), the adjusted survival rate was also significantly different between groups (85%, 80%, 55%, and 44%, respectively; RMST: P = 0.001). Survival was significantly lower in patients with moderate to severe residual TR compared to patients with mild to moderate residual TR (P = 0.006). No difference in survival rates was observed between patients with no/mild and mild to moderate residual TR (P = 0.67) or between patients with moderate to severe and severe residual TR (P = 0.96). CONCLUSIONS: The moderate residual TR group was heterogeneous and encompassed patients with markedly different clinical outcomes. Refining TR grade classification with a more granular 4-grade scheme improved outcome prediction. Our results highlight the importance of achieving a mild to moderate or lower residual TR grade during TTV repair, which could define a successful intervention.

Off-Hours Presentation, Door-to-Balloon Time, and Clinical Outcomes in Patients Referred for Primary Percutaneous Coronary Intervention.

OBJECTIVES: Presentation with ST-segment-elevation myocardial infarction (STEMI) during off-hours may impact timely reperfusion and clinical outcomes. We investigated the association between off-hours presentation, door-to-balloon time, and in-hospital mortality in patients with STEMI referred for primary percutaneous coronary intervention (PCI). METHODS: We included consecutive patients referred for primary PCI at the University of Ottawa Heart Institute between July 2004 and December 2017. The off-hours group included patients presenting on weekends, statutory holidays, or between 18:00 to 07:59 hours on weekdays. The on-hours group included patients presenting between 08:00 and 17:59 hours on weekdays. The primary clinical outcome was the adjusted in-hospital mortality. The primary quality-of-care indicator was door-to-balloon time. RESULTS: A total of 5132 patients were included, with 3152 (61.4%) in the off-hours group and 1980 (38.6%) in the on-hours group. The median door-to-balloon time was longer in the off-hours group compared with the on-hours group (102 minutes vs 77 minutes; P<.001), while the median onset-to-door time was similar (P=.40). There was no difference in the rates of in-hospital mortality (3.5% vs 3.0%; P=.32) or in the adjusted mortality (odds ratio, 1.2; 95% confidence interval, 0.8-1.8; P=.44) between off-hours and on-hours groups. However, door-to-balloon time was an independent predictor of in-hospital mortality (P<.01) and off-hours presentation was an independent predictor of longer door-to-balloon time (P<.001), with an excess of 22.1 minutes. CONCLUSION: Patients treated with primary PCI during off-hours had longer door-to-balloon times. Treatment during off-hours was an independent predictor of longer door-to-balloon time and longer door-to-balloon times were associated with higher mortality.

Fibrotic Plaque and Microvascular Dysfunction Predict Early Cardiac Allograft Vasculopathy Progression After Heart Transplantation: The Early Post Transplant Cardiac Allograft Vasculopathy Study.

BACKGROUND: Early cardiac allograft vasculopathy (CAV) prognostication is needed to improve long-term outcomes after heart transplantation. We characterized first year posttransplant coronary anatomic-physiologic alterations to determine predictors of early CAV progression. METHODS: Heart transplant recipients at 2 institutions (enrolled January 2018 to March 2021) underwent prospective evaluation 3 and 12-month posttransplant with angiography and left anterior descending artery intravascular ultrasound, optical coherence tomography, fractional flow reserve, coronary flow reserve, and index of microcirculatory resistance measurements. CAV progression was assessed by intravascular ultrasound change in percentage intimal volume from baseline to 12-month follow-up. RESULTS: Eighty-two patients (mean age, 51 years; 60% men) completed evaluation at mean 13.8 and 56.3 weeks posttransplant. Donor atherosclerosis (baseline intravascular ultrasound maximal intimal thickness, ≥0.5 mm) was evident in 50%. De novo (follow-up maximal intimal thickness, ≥0.5 mm) and rapidly progressive CAV (maximal intimal thickness, ≥0.5-mm increase from baseline) developed in 24% and 13%, respectively. On optical coherence tomography, baseline to follow-up median intimal volume increased 42% (0.58 mm3/mm), percentage intimal volume increased 44% (4.6%), vessel volume decreased 4% (-0.50 mm3/mm) and lumen volume decreased 9% (-1.02 mm3/mm); P<0.05 for all. Fibrotic plaque was the predominant morphology: baseline, 29% and follow-up, 50%. Coronary physiology was abnormal in 41% at baseline and 45% at follow-up, with 1 in 5 patients having microvascular dysfunction (index of microcirculatory resistance, ≥25). On multivariable linear regression analysis, recipient male sex, fibrotic plaque, and index of microcirculatory resistance were independent predictors of coronary disease progression. CONCLUSIONS: Fibrotic plaque on optical coherence tomography and index of microcirculatory resistance early posttransplant predict CAV progression in the first year of transplantation. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03217786.