Recent Research Publications and Funding

 Long QT syndrome (LQTS) is a hereditary disorder in which the majority of affected individuals present with QT prolongation on electrocardiograms (ECGs), arising from delayed ventricular repolarization. This commonly arrhythmia-associated genetic syndrome can lead to sudden cardiac death (SCD) and increased propensity for arrythmogenic syncope. The authors describe the case of a young patient who presented with episodes of syncope, prolonged QTc interval on ECG, and family history of SCD. He subsequently received an ICD for protection against SCD based on his prior clinical history. The article discusses the clinical manifestations, electrocardiographic (ECG) findings, management of LQTS, and role of the clinician in testing, teaching, and counseling the affected patients and families.

Aims We investigated the utility of real-time stroke volume (SV) monitoring via the arterial pulse power technique to optimize cardiac resynchronization therapy (CRT) parameters at implant and prospectively evaluated the clinical and echocardiographic results.

Methods and results Fifteen patients with ischaemic or non-ischaemic dilated cardiomyopathy, sinus rhythm, Class III congestive heart failure, and QRS >150 ms underwent baseline 2D echocardiogram (echo), 6 min walk distance, and quality of life (QOL) questionnaire within 1 week of implant. Following implant, 0.3 mmol lithium chloride was injected to calibrate SV via dilution curve. Atrioventricular (AV) delay (90, 120, 200 ms, baseline: atrial pacing only) and V-V delay (−80 to 80 ms in 20 ms increments) were varied every 60 s. The radial artery pulse power autocorrelation method (PulseCO algorithm, LiDCO, Ltd.) was used to monitor SV on a beat-to-beat basis (LiDCO, Ltd.). Optimal parameters were programmed and echo, 6 min walk, and QOL were repeated at 6–8 weeks post-implant. Nine patients had >5% increase in SV after optimization (Group A). Six patients had <5% improvement in SV (Group B). Compared with Group B, Group A had significant improvements in left ventricular ejection fraction (LVEF) (11.0 ± 8.5 vs. 0.8 ± 2.0%) and decrease in left ventricular end-diastolic dimension (LVEDD) (−0.6 ± 0.4 vs. −0.2 ± 0.2 cm) and 6 min walk (346 ± 226 vs. 32 ±271 ft, P ≤ 0.05). Group A patients also tended to have greater improvement in the septal-to-posterior wall motion delay on M-mode echo (P = 0.07).

Conclusion Real-time SV measurements can be used to optimize CRT at the time of implant. Improvement in SV correlates with improvement in LVEF, LVEDD, and 6 min walk, and improvement in echocardiographic dyssynchrony.  

 In 2009, President Obama signed an Executive Order calling for strategies to improve the health of Asian Americans and to seek data on the health disparities in Asian American subgroups.1 Data on Asian American subgroups are scarce and many health disparities remain unknown. The purpose of this Advisory is to highlight the gaps in existing research on cardiovascular disease (CVD) among Asian Americans, and to serve as a call to action on behalf of the American Heart Association to address these areas of need.

Asian Americans are the fastest growing racial/ethnic group in the United States, representing 25% of all foreign-born people in the United States.2 They are projected to reach nearly 34 million by 2050.3 Several major Federal surveys (eg, the American Community Survey, the National Health Interview Survey, and the Behavioral Risk Factor Surveillance Survey) only recently started to classify Asian Americans into 7 subgroups: Asian Indian, Chinese, Filipino, Korean, Japanese, Vietnamese, and Other Asian. The first six of these subgroups together constitute >90% of Asian Americans in the United States.4 Although some data are available on Asian subgroups from these major federal surveys, in general, these data are not available for public use because of the privacy concerns resulting from the small sample sizes within subgroups. This situation limits their utility for health-related research.

Abstract BACKGROUND: Atrial and ventriclar tachyarrhythmias, as well as bradyarrhythmias, in the elderly with heart failure (HF) and/or hypertension (HTN) have been well documented. However, the frequency of these arrhythmias, whether silent or symptomatic, and their association with subsequent cardiac events has not been well defined in patients 65 years or older with HF and other cardiovascular risk factors.

OBJECTIVE: To assess the value of 2 weeks of remote, transtelephonic cardiac monitoring for detecting arrhythmias in an elderly, urban population living with HF.

METHODS: Fifty-four patients with a history of systolic HF and/or HTN were consented and enrolled. All wore an auto triggered cardiac loop monitor for 2 weeks that captures EKG data and both silent and symptomatic arrhythmias were recorded.

RESULTS: Mean age was 73 +/- 6 years with 59% of subjects were females, 74% Hispanic, 22% black, and 4% white/other. All patients had HF and 94% had HTN. From the cardiac monitoring, 72% demonstrated ectopic atrial and ventricular activity, and 1 paroxysmal episode of atrial fibrillation was documented. In addition, 3 subjects had significant non-sustained ventricular tachycardia, and 4 individuals had severe bradycardia recorded on cardiac monitoring. These 7 individuals underwent placement of an implantable cardioverter defibrillator (ICD) or pacemaker based on the documented arrhythmias which may have otherwise gone undetected.

CONCLUSION: A substantial proportion of patients exhibited cardiac arrhythmias. Future morbidity was prevented because of the detection of arrhythmias on monitoring that led to specific therapies such as pacemaker or ICD implantation which otherwise may not have been implemented.