Philip J. Gentlesk

Sudden Death in Young Adults: An Autopsy-Based Series of a Population Undergoing Active Surveillance

OBJECTIVES The purpose of this study was to define the incidence and characterization of cardiovascular cause of sudden death in the young. BACKGROUND The epidemiology of sudden cardiac death (SCD) in young adults is based on small studies and uncontrolled observations. Identifying causes of sudden death in this population is important for guiding approaches to prevention. METHODS We performed a retrospective cohort study using demographic and autopsy data from the Department of Defense Cardiovascular Death Registry over a 10-year period comprising 15.2 million person-years of active surveillance. RESULTS We reviewed all nontraumatic sudden deaths in persons 18 years of age and over. We identified 902 subjects in whom the adjudicated cause of death was of potential cardiac etiology, with a mean age of 38 ± 11 years. The mortality rate for SCD per 100,000 person-years for the study period was 6.7 for males and 1.4 for females (p < 0.0001). Sudden death was attributed to a cardiac condition in 715 (79.3%) and was unexplained in 187 (20.7%). The incidence of sudden unexplained death (SUD) was 1.2 per 100,000 person-years for persons <35 years of age, and 2.0 per 100,000 person-years for those ≥ 35 years of age (p < 0.001). The incidence of fatal atherosclerotic coronary artery disease was 0.7 per 100,000 person-years for those <35 years of age, and 13.7 per 100,000 person-years for those ≥ 35 years of age (p < 0.001). CONCLUSIONS Prevention of sudden death in the young adult should focus on evaluation for causes known to be associated with SUD (e.g., primary arrhythmia) among persons <35 years of age, with an emphasis on atherosclerotic coronary disease in those ≥ 35 years of age.

Gender differences and risk of ventricular tachycardia or ventricular fibrillation

BACKGROUND Healthy women have longer QT intervals and more drug-induced proarrhythmia compared to men, yet those given implantable cardioverter-difibrillators (ICDs) for ischemic cardiomyopathy have fewer episodes of ventricular tachycardia/ventricular fibrillation (VT/VF) than men. The role of repolarization duration and stability in arrhythmogenesis in men and women with structural heart disease has not been explored. OBJECTIVES The purpose of this study was to analyze repolarization differences between men and women and their relation to the risk of VT/VF. METHODS Multicenter Automatic Defibrillator Trial II study patients underwent 10-minute, resting digitized recordings at study entry. QT and heart rate were measured for each beat with a semiautomated method. QT variance was normalized for mean QT (QTVN) or for heart rate variance (QTVI). Spectral analysis of heart rate and QT time series was performed; coherence was indexed to quantify consistency of heart rate and QT power spectra. The incidence of VT/VF was determined by ICD interrogation. RESULTS There were 805 usable recordings (142 females); 463 received ICDs (86 females). There was no gender difference in mean or median QT, QTc, or heart rate. QTVN and QTVI were slightly (but significantly) higher, and the mean coherence was lower in women. In a Cox multivariate analysis, increased QTVN or QTVI (top quartile) was associated with a significantly higher risk for VT/VF in men (QTVN hazard ratio (HR) 2.2; confidence interval [CI] 1.4-3.4; P = .001; QTVI HR 1.9; CI 1.2-3.0; P = .006) but not in women, while reduced coherence (bottom quartile) predicted VT/VF in women (HR 3.3; CI 1.2-9.0; P = .021) but not in men. CONCLUSIONS In post-myocardial infarcation patients with depressed ejection fraction, both women and men manifest increased temporal variability in the QT interval. In men, QT variability by itself raised arrhythmic risk. In women, however, QT variability dissociated from HR variability (low coherence) appeared to be a uniquely significant predictor of arrhythmic events.

Sinoatrial Arrest Associated With Tokutsobe Cardiomyopathy

T okutsobe cardiomyopathy, or apical ballooning syndrome, is a distinct nonischemic cardiomyopathy mimicking an ST-elevation myocardial infarction, with mid to apical left ventricular hypokinesis and basal hyperkinesis, most commonly seen in postmenopausal women and frequently associated with significantly stressful events. Most remarkable is the near complete reversal of the cardiomyopathy within a few weeks to months. Only recently have there been any reports of conduction abnormalities associated with this transient phenomenon.

High-velocity penetrating thoracic trauma with suspected cardiac involvement in a combat support hospital

PurposeThe most common cardiac injuries in the United States are blunt trauma from motor vehicle accidents or low-velocity trauma from stabbings. During military conflict, high-velocity injuries, including gunshot wounds (GSW) and fragment injury from improvised explosive devices (IED), are relatively more common.MethodsThis is a retrospective review of cases with high-velocity penetrating injury and suspected myocardial involvement during a 6-month period in Baghdad, Iraq, at a United States Army hospital during Operation Iraqi Freedom.ResultsEleven cases survived to admission (GSW in 5, IED in 6). The mean age of the all-male cohort was 27 years (range, 3–54 years). Eight of the 11 patients (73%) were victims of polytrauma. The entrance involved the right ventricle (n = 3), right atrium (n = 2), left ventricle (n = 1), or mediastinum and pericardial reflections (n = 5). Echocardiography was performed in all 11 patients. In 7 patients, no foreign body was identifiable, and in 2 patients the foreign body was identified within the pericardial fat pad. Three patients were identified as having a suspected ventricular septal defect, ranging in size from 2 to 8 mm. The most common electrocardiographic abnormality was atrioventricular block and right bundle branch block. In 4 patients, the management of the chest injury was nonsurgical, and in 1 patient the treatment was a chest tube only. Four of the patients underwent median sternotomy, 1 underwent emergent lateral thoracotomy, and 1 underwent an infradiaphragmatic approach.ConclusionThis case series is too small to draw definitive conclusions; however, a multidisciplinary approach to high-velocity injuries with potential for cardiac involvement augments preoperative assessment for myocardial injury and may allow selective nonoperative management.

Thermogenic Supplement Use Does Not Alter Characteristics of Sudden Death in the Young

Background: To evaluate supplement use, most notably ephedra, which has been temporally associated with sudden death. Animal models suggest increased myocardial irritability may predispose to primary arrhythmic death.

Management of central venous gradient using excimer laser lead extraction of chronic indwelling pacemaker leads in the setting of ipsilateral arteriovenous fistula.

Device therapy is becoming common in those patients with renal insufficiency. Coexisting need for arteriovenous (AV) fistula placement is often contemplated relative to device placement. We describe the excimer laser lead extraction of a malfunctioning chronic atrial pacemaker lead ipsilateral to an AV fistula.