Association of Physician Specialty With Long-Term Implantable Cardioverter-Defibrillator Complication and Reoperations Rates.

Background Patients undergoing implantable cardioverter-defibrillator (ICD) implantations have high rates of long-term device-related complications and reoperations. Whether physician specialty training is associated with differences in long-term outcomes following ICD implantation is unclear. Methods and Results We linked data from the National Cardiovascular Data Registry ICD Registry with Medicare fee-for-service claims to identify physicians who performed ≥10 index ICDs from 2006 to 2009. We used data from the American Board of Medical Specialties to group the specialty of the implanting physician into mutually exclusive categories: electrophysiologists, interventional cardiologists, general cardiologists, thoracic surgeons, and other specialties. Primary outcomes were long-term device-related complications requiring reoperations or hospitalizations and reoperations for reasons other than complications. We compared the cumulative incidence rates and case-mix adjusted rates of long-term outcomes of index ICD implantations across physician specialties. Our analysis had a median follow-up of 47 months and included 107 966 index ICD implantations. Electrophysiologists had the lowest rates of incident long-term device-related complications (14.1%; interventional cardiologists, 15.3%; general cardiologists, 15.4%; thoracic surgeons, 16.4%; other specialists, 15.2%; P<0.001) and reoperations for reasons other than complications (electrophysiologists, 16.7%; interventional cardiologists, 17.0%; general cardiologists, 18.0%; thoracic surgeons, 18.4%; other specialists, 18.0%; P<0.001). Compared with patients whose ICDs were implanted by electrophysiologists, patients with implantations performed by nonelectrophysiologists were at higher risk of having long-term device-related complications (relative risk for interventional cardiologists: 1.16 [95% CI, 1.08-1.25]; general cardiologists: 1.13 [1.08-1.18]; thoracic surgeons: 1.20 [1.06-1.37]; all P<0.001, but not other specialists: 1.08 [0.99-1.17]; P=0.07). Compared to patients with implantations performed by electrophysiologists, patients with implantations performed by general cardiologists and thoracic surgeons were at higher risk of reoperation for noncomplication causes (relative risk for general cardiologists: 1.10 [1.05-1.15]; thoracic surgeons: 1.16 [1.00-1.33]; both P<0.05). Conclusions Patients with ICD implantations performed by electrophysiologists had the lowest risks of having long-term device-related complications and reoperations for noncomplication causes. Consideration of physician specialty before ICD implantation may represent an opportunity to minimize long-term adverse outcomes.

Cardiac Resynchronization Defibrillator Therapy for Nonspecific Intraventricular Conduction Delay Versus Right Bundle Branch Block.

BACKGROUND: The benefits of cardiac resynchronization therapy (CRT) in patients with non-left bundle branch block (LBBB) conduction abnormality have not been fully explored. OBJECTIVES: This study sought to evaluate clinical outcomes among Medicare-aged patients with nonspecific intraventricular conduction delay (NICD) versus right bundle branch block (RBBB) in patients eligible for implantation with a CRT with defibrillator (CRT-D). METHODS: Using the National Cardiovascular Data Registry implantable cardioverter-defibrillator (ICD) registry data between 2010 and 2013, the authors compared outcomes in CRT-eligible patients implanted with CRT-D versus ICD-only therapy among patients with NICD and RBBB. Also, among all CRT-D-implanted patients, the authors compared outcomes in those with NICD versus RBBB. Survival curves and multivariable adjusted hazard ratios (HRs) were used to assess outcomes including hospitalization and death. RESULTS: In 11,505 non-LBBB CRT-eligible patients, after multivariable adjustment, among patients with RBBB, CRT-D was not associated with better outcomes, compared with ICD alone, regardless of QRS duration. Among patients with NICD and a QRS ≥150 ms, CRT-D was associated with decreased mortality at 3 years compared with ICD alone (HR: 0.602; 95% confidence interval [CI]: 0.416 to 0.871; p = 0.0071). Among 5,954 CRT-D-implanted patients, after multivariable adjustment NICD compared with RBBB was associated with lower mortality at 3 years in those with a QRS duration of ≥150 ms (HR: 0.757; 95% CI: 0.625 to 0.917; p = 0.0044). CONCLUSIONS: Among non-LBBB CRT-D-eligible patients, CRT-D implantation was associated with better outcomes compared with ICD alone specifically in NICD patients with a QRS duration of ≥150 ms. Careful patient selection should be considered for CRT-D implantation in patients with non-LBBB conduction.

A 38-Year-Old Man With Obesity, Intermittent Tachycardia, and One Episode of Syncope.

A 38-year-old man with history of diabetes, hypertension, hyperlipidemia, and obesity was referred to the electrophysiology clinic for evaluation of infrequent palpitations and remote history of syncope. The patient described a sensation of racing of the heart, which lasted about 30 min to 1 h and occurred several times over the past year. This was associated with a sense of anxiety and shortness of breath and appeared to resolve spontaneously. The patient also experienced one episode of syncope in the past while enjoying a barbecue on a hot summer day. He did not recall if this episode was accompanied by palpitations, however, the previously mentioned symptoms prompted the consultation. Upon further questioning the patient also reported experiencing fatigue. He stated that he noted decreased energy and frequent daytime sleepiness.

Outcomes of patients with definite and suspected isolated cardiac sarcoidosis treated with an implantable cardiac defibrillator.

PURPOSE: Cardiac sarcoidosis (CS) patients are at increased risk for sudden death. Isolated CS is rare and can be difficult to diagnose. METHODS: In this multicenter retrospective review, patients with CS and an implantable cardiac defibrillator (ICD) were identified. RESULTS: Of 235 patients with CS and ICD, 13 (5.5 %) had isolated CS, including 7 (3.0 %) with definite isolated CS (biopsy or necropsy-proven) and 6 (2.6 %) with suspected isolated CS based on a constellation of clinical, ECG, and imaging findings. Among 13 patients with isolated CS, 10 (76.9 %) were male, mean age was 53.8 ± 7.6 years, and mean left ventricular ejection fraction was 38.3 ± 16.5. Diagnosis was made by cardiac magnetic resonance (CMR) (n = 2), biopsy (n = 3), CMR and biopsy (n = 2), CMR and positron emission tomography (PET) (n = 2), PET (n = 1), late enhanced cardiac CT (n = 1), pathology at heart transplant (n = 1), and autopsy (n = 1). Eight of 13 (61.5 %) patients with isolated CS had a secondary prevention indication (VT in 6 and VF in 2) vs. 80 of 222 (36.0 %) with sarcoidosis in other organs (p = 0.04). Over a mean of 4.2 years, 9 of 13 (69.2 %) patients with isolated CS received appropriate ICD therapy, including anti-tachycardia pacing (ATP) and/or shock, compared with 75 of 222 (33.8 %) patients with cardiac and extracardiac sarcoidosis (p = 0.0150). Six of 7 (85.7 %) patients with definite isolated CS received appropriate ICD intervention, compared with 78 of 228 patients (34.2 %) without definite isolated CS (p = 0.0192.) CONCLUSIONS: In this retrospective study, patients with isolated CS had very high rates of appropriate ICD therapy. Prospective, long-term follow-up of consecutive patients with isolated CS is needed to determine the true natural history and rates of ventricular arrhythmias in this rare and difficult-to-diagnose disease.

Comparison of patients with peripartum heart failure and normal (≥55%) versus low (<45%) left ventricular ejection fractions.

The current definition of peripartum cardiomyopathy (PC) is restricted to patients with left ventricular systolic dysfunction (ejection fraction [EF]<45%). Data on peripartum heart failure (HF) with normal EF are sparse. We describe clinical characteristics of patients with normal (≥55%) and patients with low (<45%) left ventricular ejection fractions (LVEFs). Electronic medical records (2006 to 2013) of our tertiary care center were retrospectively screened to identify peripartum HF with normal EF, defined as an entity meeting Framingham criteria for HF with symptom onset during the last month of pregnancy or up to 5 months after delivery and with an EF of ≥55%. Clinical characteristics, echocardiographic parameters, and outcomes of these patients were compared with age-matched control patients with traditionally defined PC (EF<45%). A total of 25 patients with PC and EF≥55% were identified. Exclusion of hypertension (n=9), preeclampsia (n=1), and diabetes mellitus (n=2) yielded 13 patients with PC and EF≥55%. Age-matched patients with traditional PC (EF<45%) constituted controls (n=16). Compared with patients with PC and low LVEF, patients with PC and normal LVEF had lower B-type natriuretic peptide levels, systolic and diastolic left ventricular dimensions, left atrial size, and incidence of decompensated HF during delivery (p<0.05). Compared with historical age-matched controls, patients with normal LVEF exhibited attenuated E' mitral annular velocities. On follow-up, these patients were associated with a lower New York Heart Association functional class. In conclusion, peripartum HF with normal LVEF appears to be a distinct entity.

Efficacy and safety of implantable cardiac defibrillators for treatment of ventricular arrhythmias in patients with cardiac sarcoidosis.

AIMS: Implantable cardiac defibrillator (ICD) implantation is a class IIA recommendation for patients with cardiac sarcoidosis (CS). However, little is known about the efficacy and safety of ICDs in this population. The goal of this multicentre retrospective data review was to evaluate the efficacy and safety of ICDs in patients with CS. METHODS AND RESULTS: Electrophysiologists at academic medical centres were asked to identify consecutive patients with CS and an ICD. Clinical information, ICD therapy history, and device complications were collected for each patient. Data were collected on 235 patients from 13 institutions, 64.7% male with mean age 55.6 ± 11.1. Over a mean follow-up of 4.2 ± 4.0 years, 85 of 234 (36.2%) patients received an appropriate ICD therapy (shocks and/or anti-tachycardia pacing) and 67 of 226 (29.7%) received an appropriate shock. Fifty-seven of 235 patients (24.3%) received a total of 222 inappropriate shocks. Forty-six adverse events occurred in 41 of 235 patients (17.4%). Patients who received appropriate ICD therapies were more likely to be male (73.8 vs. 59.6%, P = 0.0330), have a history of syncope (40.5 vs. 22.5%, P = 0.0044), lower left ventricular ejection fraction (38.1 ± 15.2 vs. 48.8 ± 14.7%, P ≤ 0.0001), ventricular pacing on baseline electrocardiogram (16.1 vs. 2.1%, P = 0.0002), and a secondary prevention indication (60.7 vs. 24.5%, P < 0.0001) compared with those who did not receive appropriate ICD therapies. CONCLUSION: Patients with CS and ICDs are at high risk for ventricular arrhythmias. This population also has high rates of inappropriate shocks and device complications.

A small pericardial effusion is a marker of increased mortality.

OBJECTIVE: the study aimed to evaluate the prognostic importance of an incidental small pericardial effusion found on echocardiography. METHODS: we identified 10,067 consecutive patients undergoing echocardiography at 1 of 3 laboratories. Patients were excluded if they were referred for evaluation of the pericardium (n = 133), had cardiac surgery within the previous 60 days (n = 393), had a moderate or greater pericardial effusion (>1 cm if circumferential, n = 29), had no follow-up (n = 153), or had inadequate visualization of the pericardial space (n = 9). The Social Security Death Index was used to determine survival. RESULTS: a small pericardial effusion was noted in 534 (5.7%) of 9,350 patients. Compared to patients without a small effusion, those with an effusion were slightly older (68 ± 13 vs 67 ± 12 years, P = .02) and had a lower ejection fraction (52% vs 55%, P < .0001). Mortality at 1 year was greater for patients with a small effusion (26%) compared to those without an effusion (11%, P < .0001). After adjustment for demographics, medical history, patient location, and other echocardiographic findings, small pericardial effusion remained associated with higher mortality (hazard ratio 1.17, 95% CI 1.09-1.28, P = .0002). Of 211 with an effusion and follow-up echocardiography (mean 547 days), 136 (60%) had resolution, 63 (28%) showed no change, and 12 (5%) had an increase in size, although no patient developed a large effusion or cardiac tamponade. CONCLUSION: the presence of a small asymptomatic pericardial effusion is associated with increased mortality.

Rest premature ventricular contractions on routine ECG and prognosis in heart failure patients.

BACKGROUND: Premature ventricular contractions (PVC) at rest are frequently seen in heart failure (HF) patients but conflicting data exist regarding their importance for cardiovascular (CV) mortality. This study aims to evaluate the prognostic value of rest PVCs on an electrocardiogram (ECG) in patients with a history of clinical HF. METHODS AND RESULTS: We considered 352 patients (64 + or - 11 years; 7 females) with a history of clinical HF undergoing treadmill testing for clinical reasons at the Veterans Affairs Palo Alto Health Care System (VAPAHCS) (1987-2007). Patients with rest PVCs were defined as having > or = 1 PVC on the ECG prior to testing (n = 29; 8%). During a median follow-up period of 6.2 years, there were 178 deaths of which 76 (42.6%) were due to CV causes. At baseline, compared to patients without rest PVCs, those with rest PVCs had a lower ejection fraction (EF) (30% vs 45%) and the prevalence of EF < or = 35% was higher (75% vs 41%). They were more likely to have smoked (76% vs 55%).The all-cause and CV mortality rates were significantly higher in the rest PVCs group (72% vs 49%, P = 0.01 and 45% vs 20%, P = 0.002; respectively). After adjusting for age, beta-blocker use, rest ECG findings, resting heart rate (HR), EF, maximal systolic blood pressure, peak HR, and exercise capacity, rest PVC was associated with a 5.5-fold increased risk of CV mortality (P = 0.004). Considering the presence of PVCs during exercise and/or recovery did not affect our results. CONCLUSION: The presence of PVC on an ECG is a powerful predictor of CV mortality even after adjusting for confounding factors.

Exercise capacity at submaximal heart rate and prognosis.

INTRODUCTION: Submaximal exercise testing can be useful for individuals with limitations to performing maximal exercise. Recent studies suggested that a low workload at a heart rate 100 beats/minute (HR(100)) was associated with a greater risk of cardiovascular (CV) mortality than maximal exercise capacity. This study evaluated the prognostic value of METs achieved at HR(100) (METs(100)) in patients referred for treadmill testing. METHOD: We studied 1446 patients (56+/-12 years; 76 females) without heart failure or beta-blockers treatment (1997-2004). RESULTS: During a period of 7.0+/-2.3 years, 35 (2.5%) patients died from CV causes. Compared to survivors, the non-survivors were older (69+/-9 vs. 56+/-12 years, p<0.001); had a higher prevalence of diabetes (27% vs. 14%, p=0.04), coronary artery disease (57% vs. 25%, p<0.05) and stroke (9% vs. 2%, p<0.001). Non-survivors had lower Duke Treadmill Scores (DTS) (2.8+/-6.8 vs. 9.7+/-5.5; p<0.001) and exercise capacity (7.5+/-3.3 vs.11.0+/-3.8 METs, p<0.001). At HR(100), METs (median (range): 3.8 (2.8-4.0) vs. 3.5 (3.3-3.5)) and %HR reserve achieved (45+/-13% vs. 34+/-17%; p<0.001) were higher in non-survivors. In Cox model, age-adjusted METs(100) was not a significant predictor of CV mortality. In contrast, each one MET increase in exercise capacity was associated with a 17% increase in survival (HR=0.83, 95% CI 0.73-0.93, p=0.002). DTS was also a significant predictor of CV mortality. CONCLUSION: In our population, METs at HR(100) was not a significant predictor of CV mortality.

Adding an electrocardiogram to the pre-participation examination in competitive athletes: a systematic review.

No matter how rare, the death of young athletes is a tragedy. Can it be prevented? The European experience suggests that adding the electrocardiogram (ECG) to the standard medical and family history and physical examination can decrease cardiac deaths by 90%. However, there has not been a randomized trial to demonstrate such a reduction. While there are obvious differences between the European and American experiences with athletes including very differing causes of athletic deaths, some would highlight the European emphasis on public welfare vs the protection of personal rights in the USA. Even the authors of this systematic review have differing interpretation of the data: some of us view screening as a hopeless battle against Bayes, while others feel that the ECG can save lives. What we all agree on is that the USA should implement the American Heart Association 12-point screening recommendations and that, before ECG screening is mandated, we need to gather more data and optimize ECG criteria for screening young athletes.

The blood pressure response to dynamic exercise testing: a systematic review.

Although blood pressure (BP) is measured routinely during exercise testing, its clinical significance is not fully understood or appreciated. As the number of studies has increased, conflicting data have emerged, partly due to differences in methodologies, populations studied, testing procedures, and definitions used for an abnormal BP response. This article attempts to review the literature studying the physiology and pathophysiology of the BP response to exercise testing and summarize the evidence for its diagnostic and prognostic applications.