ABSTRACT
Stress-induced cardiomyopathy, also known as Takotsubo cardiomyopathy (TTS), is characterized by transient regional systolic dysfunction. Furthermore, electrocardiogram (ECG) changes can vary as TTS evolves. We report a case of a 67-year-old woman who presented to the ER after cardiac arrest. She was found to have stress-induced cardiomyopathy with prolonged QTc interval. The patient developed torsades de pointes for which she required cardioversion, followed by improvement of QTc interval corresponding to resolution of echocardiographic evidence of apical ballooning.
ABSTRACT
Premature ventricular complexes (PVCs) are one of the most commonly encountered arrhythmias and are ubiquitous in clinical practice, both in the outpatient and inpatient settings. They are often discovered incidentally in asymptomatic patients, however, can cause myriad symptoms acutely and chronically. Long thought to be completely benign, PVCs have been historically disregarded without pursuing any further evaluation. Newer data have revealed that a high burden of PVCs with specific characteristics can significantly increase a patient's risk of developing PVC-induced cardiomyopathy. The aim of this literature review is to provide further clarification on the identification of high-risk PVCs, subsequent workup, and the currently available treatment options. PVCs arise from an ectopic focus within the ventricles. Patients with PVCs can be either asymptomatic or have severe disabling symptoms. The diagnostic workup for PVCs includes electrocardiogram (ECG) and 24-h Holter monitor to assess the QRS morphology and its frequency. A transthoracic echocardiogram (TTE) is done to look for structural heart disease and cardiomyopathy. Management of PVCs should be focused on identifying and treating the underlying causes, such as electrolyte abnormalities, substance use, and underlying structural heart disease. Beta-blockers are first-line therapy for symptomatic PVCs. Nondihydropyridine calcium channel blockers, classic antiarrhythmic agents, and amiodarone can be considered as second-line agents. Patients who are unable to tolerate medical therapy should undergo catheter ablation of the PVC focus to prevent PVC-induced cardiomyopathy. PVCs are common in clinical practice, and it is vital to identify patients at higher risk for PVC-induced cardiomyopathy to facilitate early intervention. Patients with no evidence of structural heart disease and infrequent PVCs should be monitored closely, while those who are symptomatic should be treated medically. For those who have failed medical therapy, catheter ablation of the PVCs focus is recommended. Catheter ablation has been shown to reduce PVCs burden and improve left ventricular ejection fraction (LVEF) in those with PVC-induced cardiomyopathy.
ABSTRACT
BACKGROUND: Chagas disease is a well-known cause of cardiomyopathy in Latin America; however, 300 000 individuals are estimated to have Chagas disease in the United States. This study examined the prevalence and impact of Chagas cardiomyopathy (CCM) in a US population. We hypothesized that patients with CCM would have increased morbidity and mortality when compared with patients with non-CCM. METHODS AND RESULTS: This is a single-center, prospective cohort study. Enrollment criteria were new diagnosis of nonischemic cardiomyopathy (left ventricular ejection fraction ≤40%) and previous residence in Latin America for at least 12 months. Serological testing for Trypanosoma cruzi was performed at enrollment. The primary end point was all-cause mortality or heart transplantation. The secondary end point was heart failure-related hospitalization. A total of 135 patients were enrolled, with a median of 43 months of follow-up. Chagas disease was diagnosed in 25 (19%) patients. The primary end point occurred in 9 patients (36%) in the CCM group and in 11 patients (10%) in the non-CCM group (hazard ratio [HR], 4.46; 95% confidence interval, 1.8-10.8; P=0.001). The secondary end point occurred in 13 patients (52%) in the CCM group and in 35 patients (32%) in the non-CCM group (HR, 2.22; 95% confidence interval, 1.2-4.2; P=0.01). CONCLUSIONS: There is a high prevalence of Chagas disease among Latin American immigrants diagnosed with nonischemic cardiomyopathy in Los Angeles. Advanced CCM portends a poor prognosis and is associated with increased all-cause mortality/heart transplantation and heart failure-related hospitalization.
Subject(s)
Cardiomyopathies/ethnology , Chagas Disease/ethnology , Emigrants and Immigrants , Aged , California/epidemiology , Female , Follow-Up Studies , Humans , Latin America/ethnology , Male , Middle Aged , Prevalence , Prospective StudiesABSTRACT
The use of continuous-flow left ventricular assist devices (LVAD) have markedly improved outcomes in patients with advanced heart failure (HF). The HeartWare LVAD is a miniaturized centrifugal pump implanted within the pericardial space. Implantable cardioverter-defibrillators (ICDs) are susceptible to oversensing of extracardiac signals (electromagnetic interference [EMI]). We report two cases of EMI in patients that received a HeartWare LVAD as destination therapy for advanced HF. The patients were 75 and 78 years old, both with severe ischemic dilated cardiomyopathy (ejection fraction < 0.20) and New York Heart Association class 4 heart failure. Both patients had a St. Jude Medical Unify ICD with a 7 Fr dual coil St. Jude Medical Durata ICD lead. In both patients, the lead location was in the right ventricular apex with an inferior orientation. Both patients experienced immediate ICD therapies after LVAD placement, requiring the tachytherapies to be disabled. ICD programming changes to increase sensitivity and the detection windows were ineffective. Both patients underwent ICD system revision. In one patient, the existing lead was moved to an anteroseptal location that stopped the EMI. In the other patient, the ICD system was changed to allow a separate right ventricular sensing lead in an anteroseptal location and a dual coil ICD lead placed in an apical location, a strategy used to obtain an acceptable defibrillation threshold. The patients have had no subsequent EMI detected on clinical and remote monitoring. Patients with a right ventricular apical ICD lead placement that undergo placement of a HeartWare LVAD are susceptible to EMI and inappropriate ICD therapies. These cases suggest the primary mechanism is proximity of the ICD lead to the device and as such relocation to an anteroseptal location can overcome the problem. These data suggest that all patients that receive a HeartWare LVAD with an ICD should have the device carefully checked at maximum LVAD output to determine if EMI may be present. ASAIO Journal 2013;59:136-139. Key Words: left ventricular assist device, electromagnetic interference, improper ICD shocks, end-stage heart failure.