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Patients with hypertrophic cardiomyopathy (HCM) are at risk of sudden death, and individuals with ≥1 major risk markers are considered for primary prevention implantable cardioverter-defibrillators. Guidelines recommend cardiac magnetic resonance (CMR) imaging to identify high-risk imaging features. However, CMR imaging is resource intensive and is not widely accessible worldwide. The purpose of this study was to develop electrocardiogram (ECG) deep-learning (DL) models for the identification of patients with HCM and high-risk imaging features. Patients with HCM evaluated at Tufts Medical Center (N = 1930; Boston, MA) were used to develop ECG-DL models for the prediction of high-risk imaging features: systolic dysfunction, massive hypertrophy (≥30 mm), apical aneurysm, and extensive late gadolinium enhancement. ECG-DL models were externally validated in a cohort of patients with HCM from the Amrita Hospital HCM Center (N = 233; Kochi, India). ECG-DL models reliably identified high-risk features (systolic dysfunction, massive hypertrophy, apical aneurysm, and extensive late gadolinium enhancement) during holdout testing (c-statistic 0.72, 0.83, 0.93, and 0.76) and external validation (c-statistic 0.71, 0.76, 0.91, and 0.68). A hypothetical screening strategy using echocardiography combined with ECG-DL–guided selective CMR use demonstrated a sensitivity of 97% for identifying patients with high-risk features while reducing the number of recommended CMRs by 61%. The negative predictive value with this screening strategy for the absence of high-risk features in patients without ECG-DL recommendation for CMR was 99.5%. In HCM, novel ECG-DL models reliably identified patients with high-risk imaging features while offering the potential to reduce CMR testing requirements in underresourced areas. [Display omitted] [ABSTRACT FROM AUTHOR]

This case describes a 74-year-old male who presented with rapid atrial flutter in association with large atrial lipoma along the interatrial septum. Conversion to sinus rhythm revealed the electrocardiographic criteria for advanced interatrial block. Interatrial block results from disruption of conduction through Bachmann's bundle, most commonly due to progressive atrial fibrosis. Bayés syndrome is recognized as the association of atrial arrhythmias with underlying interatrial block. This case supports the concept that localized disruption of atrial conduction via Bachmann's bundle from an atrial lipoma can produce the electrophysiologic substrate for atrial arrhythmias and the Bayés syndrome. [ABSTRACT FROM AUTHOR]

Moderate-intensity exercise improves cardiovascular outcomes. However, mounting clinical evidence demonstrates that long-term, high-intensity endurance training predisposes male and veteran athletes to an increased risk of atrial fibrillation (AF), a risk that is not observed across both genders. Although increased mortality associated with AF in the general population is not shared by athletes, clinically significant morbidities exist (eg, reduced exercise capacity, athletic performance, and quality of life). Additional research is needed to fill current gaps in knowledge pertaining to the natural history, pathophysiologic mechanisms, and management strategies of AF in the athlete. [ABSTRACT FROM AUTHOR]

The convergent procedure is a hybrid ablation treatment for atrial fibrillation. It is increasingly considered as a management option for patients with persistent and long-standing atrial fibrillation. It consists of surgical ablation of the posterior left atrium through a minimally invasive closed-chest approach followed by endocardial catheter ablation. It is increasingly performed with concurrent epicardial occlusion of the left atrial appendage with a video-assisted thoracoscopic technique to physically and electrically isolate the left atrial appendage. This article provides an overview of a multidisciplinary approach to the convergent procedure, with concurrent thoracoscopic closure of the left atrial appendage, with an emphasis on perioperative management at a single institution. It provides a literature review of procedural outcomes, current data limitations, and future considerations. [ABSTRACT FROM AUTHOR]

Background: The introduction of quadripolar (QP) cardiac resynchronization therapy (CRT) leads aimed to improve procedural and clinical outcomes.Objective: The National Cardiovascular Data Registry was analyzed to characterize the use as well as the procedural and clinical outcomes of QP leads in comparison with unipolar and bipolar (BP) leads.Methods: We evaluated data on 175,684 procedures reported between September 1, 2010, and December 31, 2015. Clinical outcomes were analyzed using Centers for Medicare & Medicaid Services claims data.Results: Among all CRT device implants, there was a drop in reported lead placement failure from 6.04% to 5.21% (P < .0001 for trend) and a drop in the reported diaphragmatic stimulation rates from 0.07% to 0.01% (P < .007 for trend) between the last quarters of 2010 and 2015. No significant difference in procedural complication rates between QP and BP leads occurred (1.34% and 1.39%, respectively; P = .50). Among patients linked to Centers for Medicare & Medicaid Services claims data, no statistically significant difference in the combined primary outcome of death, congestive heart failure admission, device malfunction, and reoperation between BP and QP leads was observed (34.15 and 34.19 events per 100 patient-years, respectively; P = .89).Conclusion: Since the introduction of QP leads, there was a reduction in CRT lead placement failure rates and a reduction in diaphragmatic stimulation rates. However, no statistically significant difference in long-term clinical outcomes between BP and QP leads was observed in elderly patients undergoing CRT implantation. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common atrial arrhythmia in adults worldwide. As medical advancements continue to contribute to an ever-increasing aging population, the burden of atrial fibrillation on the modern health care system continues to increase. Therapies are also evolving, for treatment of the arrhythmia itself, and stroke risk mitigation. Internists and cardiologists alike are, in most instances, the frontline contact for AF patients, and would benefit from remaining facile in their understanding of care options. To continue to deliver high-quality care to this expanding patient group, an updated, concise review for the clinician is prudent. This article provides a comprehensive summary of the current epidemiology and pathophysiology of AF, as well as contemporary procedural therapeutic options. [ABSTRACT FROM AUTHOR]

Background: Sudden death due to low-energy blunt trauma to the precordium (commotio cordis) has been described with a variety of sporting objects. However, the risk of ventricular fibrillation (VF) relative to the shape of the impact object is not known.Objective: The objective of the current experiment is to test whether the impact object shape is a clinical variable that affects the risk for commotio cordis.Methods: In a juvenile swine model, impacts were given in random order with two different spherical shapes (72 mm diameter, equivalent to a baseball; 42 mm diameter, equivalent to a golf ball) and a flat round object 72 mm in diameter. Objects were equal in weight (150 g), thrown at 30 mph, and gated to the vulnerable portion of the cardiac cycle.Results: Sixteen swine received 144 impacts. The flat object did not cause VF (P = .01 compared with the two spherical objects), nonsustained VF, ST elevation, or bundle branch block. The smaller diameter sphere caused VF in nine of 48 impacts (19%), and the larger diameter sphere caused VF in five of 48 impacts (10%; P = .25). The smaller diameter sphere was associated with a greater increase in left ventricular pressure (P <.0001 and P = .001 compared with larger sphere only) and a higher likelihood of ST segment elevations (P <.001 and P = .08 compared with larger sphere only) and bundle branch block (Fisher's exact P = .008, and Fisher's exact P = .18 compared with larger sphere only).Conclusion: The shape of the projectile markedly influences the risk of VF from chest wall impact. This effect is likely mediated via a greater increase in left ventricular pressure with smaller diameter objects. Spreading the impact force over a larger area may decrease the risk of sudden death and has implications for the design of protective athletic equipment. [ABSTRACT FROM AUTHOR]

Background: Stress cardiomyopathy (SCM) is a syndrome of transient ventricular dysfunction triggered by severe emotional or physical stress, likely resulting from catecholamine-mediated myocardial toxicity. Repolarization abnormalities associated with other hyperadrenergic states can cause QT prolongation and lethal arrhythmia including torsades de pointes (TdP). Despite the development of repolarization abnormalities and QT prolongation in SCM, little is known about the risk of ventricular fibrillation (VF) and TdP. Objective: The aim of this study was to assess the prevalence and clinical predictors of ventricular arrhythmias in a cohort of patients with SCM. Methods: Data from a registry of consecutive patients with SCM from 2 institutions were reviewed. Patients who developed VF or TdP were identified. Clinical characteristics and outcomes were analyzed and compared with a control group of patients with SCM without VF/TdP. Results: Of 93 patients with SCM, 8 (8.6%) experienced VF/TdP. Of these 8 patients, 2 presented with VF and were subsequently diagnosed with SCM. Six other patients experienced pause-dependent TdP or VF after SCM diagnosis in the setting of substantial QT prolongation. Prolongation of the corrected QT interval (QTc) was significantly associated with the occurrence of ventricular arrhythmia (odds ratio 1.28 for each 10 ms increase in QTc, 95% confidence interval 1.10 to 1.50). Conclusion: SCM can be associated with life-threatening ventricular arrhythmia in over 8% of cases. SCM should be recognized among the causes of acquired long QT syndrome and can be associated with a risk of TdP. [ABSTRACT FROM AUTHOR]

Multiple randomized controlled trials (RCTs) have established the efficacy of statins for the prevention of cardiovascular disease. The benefits observed are often framed in terms of percentage reductions in low-density lipoprotein (LDL) cholesterol from baseline or percentage reductions between control and treatment groups, although epidemiologic data suggest that the absolute intergroup difference in LDL cholesterol (ΔLDLControl-Rx) is the more informative measure. A systematic review of large-scale trials of statins versus placebo, usual care, or active (lower dose statin) control was conducted to calculate updated summary estimates of risk reduction in coronary artery disease and all-cause mortality. Meta–regression analysis was used to ascertain the relations of different LDL cholesterol metrics to outcomes. In 20 eligible RCTs, there were significant overall reductions for coronary artery disease (odds ratio 0.72, 95% confidence interval 0.67 to 0.78) and mortality (odds ratio 0.89, 95% confidence interval 0.84 to 0.94), but with substantial variability in trial results. ΔLDLControl-Rx was the strongest determinant of coronary artery disease risk reduction, particularly after excluding active-comparator studies, and was independent of baseline LDL cholesterol. In contrast, baseline LDL cholesterol edged out ΔLDLControl-Rx as the strongest determinant of mortality, but neither was significant after the exclusion of active-comparator studies. The exclusion of 3 RCTs involving distinct populations, however, rendered ΔLDLControl-Rx the predominant determinant of mortality reduction. In conclusion, these findings underscore the primacy of absolute reductions in LDL cholesterol in the design and interpretation of RCTs of lipid-lowering therapies and in framing treatment recommendations on the basis of the proved coronary benefits of these drugs. [Copyright &y& Elsevier]

Background: Precordial thump for cardiac arrest remains controversial. Although precordial blows can trigger ventricular fibrillation (VF) (i.e., commotio cordis), they paradoxically have been regarded as potential therapy for cardiac arrest. In commotio cordis, impact energy and resultant peak left ventricular (LV) pressure are important variables in VF initiation. Objective: The purpose of this study was to assess the relationship between LV pressures generated by thumps and their effectiveness in defibrillation of VF or resuscitation of asystole after defibrillation. Methods: After induction of VF, 10 swine each received 18 chest thumps; two sets of three thumps each with a clenched fist, a 30-mph lacrosse ball, and a 40-mph lacrosse ball. If asystole followed defibrillation, manual thumps were given to induce ventricular depolarizations until resumption of spontaneous rhythm. Results: During VF, generated LV pressure (mmHg) was 263 ± 52 with manual thumps, 392 ± 179 with 30-mph ball thumps, and 616 ± 182 with 40-mph ball thumps (P <.001). None of the 180 thumps terminated VF. All episodes required electrical defibrillation. During asystole, generated LV pressures were greater for thumps that induced ventricular depolarizations than for those that did not (111 ± 27 mmHg vs 73 ± 23 mmHg, P <.001). A significant association was observed between induction of ventricular depolarizations and thump-generated LV pressures (odds ratio 2.0 per 10 mmHg rise in LV pressure, 95% confidence interval 1.8–2.1). Conclusion: Despite generating high LV pressures, precordial thumps were not effective in terminating VF. Based on these data, precordial thump for VF in cardiac arrest victims cannot be recommended but for asystolic victims might be beneficial. [Copyright &y& Elsevier]

Transient stress cardiomyopathy (TSC) is a cause of reversible left ventricular (LV) dysfunction that is increasingly recognized. Reports to date have focused primarily on LV involvement, with little attention paid to associated right ventricular (RV) dysfunction. With other forms of LV dysfunction, RV involvement has been shown to confer an adverse prognosis. Prevalence, clinical characteristics, and short-term prognosis of RV dysfunction in TSC remain ill-defined. Presenting echocardiograms of 40 patients with TSC were reviewed. RV function was assessed by evaluating regional wall motion and calculating a wall motion score index (WMSI). RV dysfunction was defined as a WMSI >1.0. Clinical and demographic characteristics of patients with and without RV dysfunction were compared. RV dysfunction was identified in 27% of patients (11 of 40). RV WMSI was 1.20 ± 0.30 for the entire cohort compared with 1.72 ± 0.30 for those with RV dysfunction (p <0.05). In each case with RV dysfunction, regional wall motion abnormalities involved the apex and spared the base. Patients with RV dysfunction had higher B-type natriuretic peptide levels, higher pulmonary artery systolic pressures, and longer hospital stays. RV dimensions, clinical characteristics, electrocardiographic findings, other biomarkers, and in-hospital complications were similar. In conclusion, RV wall motion abnormalities, predominantly involving the apex and sparing the base, occur in slightly >1/4 of cases of TSC. Although associated with higher B-type natriuretic peptide levels, higher pulmonary artery systolic pressures, and longer hospital stays, RV dysfunction was not associated with significant differences in short-term cardiac morbidity or increased early mortality. [Copyright &y& Elsevier]

The Food and Drug Administration has banned the sale of ephedrine-based weight-loss products because of their association with many cardiovascular adverse effects. Bitter orange is now being used as a stimulant in "ephedra-free" weight-loss supplements but was recently implicated in adverse cardiovascular sequelae. To our knowledge, this report describes the first case of variant angina associated with bitter orange in a dietary supplement. [ABSTRACT FROM AUTHOR]

A response from Christopher A. Gange, Christopher Madias, Andrew R. Weintraub, N. A. Mark Estes III and Erika M. Felix-Getzik to a letter to the editor about their article "Reporting Associations Between Dietary Supplements and Adverse Events" in the April 2006 issue.

The CHA(2)DS(2)-VASc and CHADS(2) risk stratification schemes are used to predict thromboembolism and ischemic stroke in patients with atrial fibrillation. However, limited data are available regarding the utility of these risk stratification schemes for stroke in patients with atrial flutter. A retrospective analysis of 455 transesophageal echocardiographic studies in patients with atrial flutter was performed to identify left atrial (LA) thrombi and/or spontaneous echocardiographic contrast (SEC). The CHA(2)DS(2)-VASc (Congestive heart failure, Hypertension, Age ≥75 years [doubled risk weight], Diabetes mellitus, previous Stroke/transient ischemic attack [doubled risk weight], Vascular disease, Age 65 to 74 years, Sex) and CHADS(2) (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, previous Stroke/transient ischemic attack [double risk weight]) scores were calculated to stratify the risk of stroke or transient cerebrovascular ischemic events. Transesophageal echocardiography revealed LA thrombi in 5.3% and SEC in 25.9% of patients. Using CHADS(2), LA thrombus was found in 2.2% of the low-intermediate-risk group and 8.3% of the high-risk group (p = 0.005). SEC was found in 19.8% of the low-intermediate-risk group and 32% of the high-risk group (p = 0.004). Using CHA(2)DS(2)-VASc, LA thrombus was found in 1.7% of the low-intermediate-risk group and 6.5% of the high-risk group (p = 0.053). SEC was found in 11.8% of the low-intermediate-risk group versus 30.9% of the high-risk group (p = 0.004). The sensitivity for LA thrombus/SEC with a high CHADS(2) and CHA(2)DS(2)-VASc score was 64.8% and 88.7%, respectively (p = 0.0001). The specificity for LA thrombus/SEC with high CHADS(2) and CHA(2)DS(2)-VASc scores was 52.6% and 28.9%, respectively (p = 0.0001). In conclusion, both CHA(2)DS(2)-VASc and CHADS(2) scores are useful for stroke risk stratification in patients with atrial flutter. CHA(2)DS(2)-VASc had greater sensitivity for LA thrombus and SEC detection at the cost of reduced specificity. [ABSTRACT FROM AUTHOR]

The CHA2DS2-VASc and CHADS2 risk stratification schemes are used to predict thromboembolism and ischemic stroke in patients with atrial fibrillation. However, limited data are available regarding the utility of these risk stratification schemes for stroke in patients with atrial flutter. A retrospective analysis of 455 transesophageal echocardiographic studies in patients with atrial flutter was performed to identify left atrial (LA) thrombi and/or spontaneous echocardiographic contrast (SEC). The CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ≥75 years [doubled risk weight], Diabetes mellitus, previous Stroke/transient ischemic attack [doubled risk weight], Vascular disease, Age 65 to 74 years, Sex) and CHADS2 (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, previous Stroke/transient ischemic attack [double risk weight]) scores were calculated to stratify the risk of stroke or transient cerebrovascular ischemic events. Transesophageal echocardiography revealed LA thrombi in 5.3% and SEC in 25.9% of patients. Using CHADS2, LA thrombus was found in 2.2% of the low–intermediate-risk group and 8.3% of the high-risk group (p = 0.005). SEC was found in 19.8% of the low–intermediate-risk group and 32% of the high-risk group (p = 0.004). Using CHA2DS2-VASc, LA thrombus was found in 1.7% of the low–intermediate-risk group and 6.5% of the high-risk group (p = 0.053). SEC was found in 11.8% of the low–intermediate-risk group versus 30.9% of the high-risk group (p = 0.004). The sensitivity for LA thrombus/SEC with a high CHADS2 and CHA2DS2-VASc score was 64.8% and 88.7%, respectively (p = 0.0001). The specificity for LA thrombus/SEC with high CHADS2 and CHA2DS2-VASc scores was 52.6% and 28.9%, respectively (p = 0.0001). In conclusion, both CHA2DS2-VASc and CHADS2 scores are useful for stroke risk stratification in patients with atrial flutter. CHA2DS2-VASc had greater sensitivity for LA thrombus and SEC detection at the cost of reduced specificity. [ABSTRACT FROM AUTHOR]