Concurrent Assessment of the CardioMEMS HF System and HeartLogic HF Diagnostic: A Retrospective Case Series.

BACKGROUND: Heart failure (HF) causes high morbidity and mortality despite advances in medical therapy. Remote patient monitoring for HF allows for the optimization of medical therapy and prevention of HF hospitalizations. This study is the first to assess pulmonary artery diastolic pressures (PADP) using the CardioMEMS HF System (CMEMS) and cardiac implantable electronic device-based multisensor indexes (HeartLogic index [HLI]) using the HeartLogic HF Diagnostic (HL) in a small, retrospective cohort of patients with HF at a single center. METHODS AND RESULTS: Any hospitalization, HF hospitalization, HF-related outpatient visit, and pulmonary artery pressure action were recorded in 7 patients with concurrent CMEMS and HL measurements for at least 1 year. The median time before both platforms were implanted and present in the same participant was 3.12 months. The median study period was 1.44 years per participant. Data availability for HL was significantly higher at 99.6% compared with 64.1% adherence for CMEMS (P = .016). Overall, PADP was only weakly correlated to HLI (r = 0.098), but there was a 2.87 mm Hg (P = .014) estimated increase in PADP during HLI alert periods versus nonalert periods. Similarly, the estimated odds of being above a PADP goal was 4.7 times higher (95% confidence interval 3.0-7.2, P < .001) in HLI alert vs nonalert periods. CONCLUSIONS: Concurrent analysis of patients with CMEMS and HL showed an association between PADP and HLI, but the correlation was weak. However, there was a significant increase in PADP during HLI alert periods versus nonalert periods.

Development and implementation of a remote patient monitoring program for heart failure: a single-centre experience.

AIMS: Remote patient monitoring (RPM) in the management of heart failure (HF), including telemonitoring, thoracic impedance, implantable pulmonary artery pressure (PAP) monitors, and cardiac implantable electronic device (CIED)-based sensors, has had varying outcomes in single platform studies. Uncertainty remains regarding the development of single-centre RPM programs; additionally, no studies examine the effectiveness of dual platform RPM programs for HF. This study describes the implementation and outcomes of a dual platform RPM program for HF at a single centre. METHODS AND RESULTS: An RPM program was developed to include two platforms (e.g. CardioMEMS™ HF System and HeartLogic™ HF Diagnostic). To examine changes within each participant over time, study-related outcomes including total hospitalizations (TH), total length of stay (TLOS), cardiac hospitalizations (CH), cardiac LOS (CLOS), and cardiac-related emergency department (ED) visits were compared in two timeframes: 12 months pre-enrolment and post-enrolment into RPM. For 141 participants enrolled, there was a significant reduction in the likelihood of experiencing a CH by 19% (0.77 vs. 0.61 events/patient-year; HR: 0.81, 95% CI: 0.67-0.97, P = 0.03) and a cardiac-related ED visit by 28% (0.48 vs. 0.34 events/patient-year; HR: 0.72, 95% CI: 0.55-0.93, P = 0.01). There was also a 51% decrease (SE = 1.41, 95% CI: 2.79-8.38 days, P < 0.001) and 62% decrease (SE = 1.24, 95% CI: 3.35-8.22 days, P < 0.001) in TLOS and CLOS, respectively. CONCLUSIONS: A dual platform RPM program for HF using structured education, RPM-capable devices, and alert-specific medication titration reduces the likelihood of experiencing a cardiac hospitalization and cardiac-related ED visit in this single-centre study.

Arrhythmogenic substrate of the pulmonary veins assessed by high-resolution optical mapping.

BACKGROUND: It has recently been recognized that atrial fibrillation can originate from focal sources in the pulmonary veins (PVs). However, the mechanisms of focal atrial fibrillation have not been well characterized. We assessed the electrophysiological characteristics of the PVs using high-resolution optical mapping. METHODS AND RESULTS: Coronary-perfused, isolated whole-atrial preparations from 33 normal dogs were studied. Programmed electrical stimulation was performed, and a 4-cm2 area of the PV underwent optical mapping of transmembrane voltage to obtain 256 simultaneous action potentials. Marked conduction slowing was seen at the proximal PV, compared with the rest of the vein, on both the epicardial (31.3+/-4.47 versus 90.2+/-20.7 cm/s, P=0.001) and endocardial (45.8+/-6.90 versus 67.6+/-10.4 cm/s, P=0.012) aspects. Pronounced repolarization heterogeneity was also noted, with action potential duration at 80% repolarization being longest at the PV endocardium. Nonsustained reentrant beats were induced with single extrastimuli, and the complete reentrant loop was visualized (cycle length, 155+/-30.3 ms); reentrant activity could be sustained with isoproterenol. Sustained focal discharge (cycle length, 330 to 1100 ms) was seen from the endocardial surface in the presence of isoproterenol; each focus was localized near the venous ostium. CONCLUSIONS: The normal PV seems to have the necessary substrate to support reentry as well as focal activity. Although reentry occurred more distally in the vein, focal activity seemed to occur more proximally.

Incremental value of myocardial viability for prediction of long-term prognosis in surgically revascularized patients with left ventricular dysfunction.

OBJECTIVES: We assessed the incremental long-term prognostic value of myocardial viability in surgically revascularized (CABG) patients with left ventricular (LV) dysfunction. BACKGROUND: Clinical factors, medical therapy, the degree of LV dysfunction, and stress-induced ischemia may affect the relative prognostic value of myocardial viability. METHODS: Patients with coronary disease and ventricular dysfunction (mean ejection fraction 33% by echocardiography, 25% by angiography) were studied with dobutamine echocardiography. Follow-up (mean -4.9 years) was obtained in 95 patients (85% triple-vessel disease) who underwent CABG. RESULTS: The use of angiotensin-converting enzyme inhibitors, advanced heart failure, rest, low- and peak-dose wall motion scores were univariate predictors of cardiac death. The extent of contractile reserve and ischemia were not predictive. Low-dose score was the strongest multivariate predictor of death (p < 0.001, hazard ratio 6.7). A biphasic response predicted better survival (p = 0.045, hazard ratio 0.5). Five-year survival was better in those with extensive (low-dose score <2.00) versus intermediate (score 2.00 to 2.49) amounts of viable myocardium (p = 0.019). Patients with the least viability (score > or =2.5) had the worst outcome (p = 0.0001 vs. those with low-dose score <2.00; p = 0.05 vs. those with score 2.00 to 2.49). In stepwise multivariate analysis, low-dose score added incremental prognostic value (p = 0.024) to clinical information and rest score. CONCLUSIONS: Low-dose score, representing the extent of viable myocardium, has incremental prognostic value as a predictor of long-term outcome in CABG patients with LV dysfunction.

Reduced right ventricular systolic function in constrictive pericarditis indicates myocardial involvement and persistent right ventricular dysfunction and symptoms after pericardiectomy.

We report four cases of patients with documented constrictive pericarditis who had evidence of reduced right ventricular (RV) systolic function. Assessment of RV systolic function was performed by pulsed tissue Doppler sampling of basal RV free wall velocity at the level of the tricuspid annulus in the four-chamber view. Velocity values and time velocity integral calculated from the velocity envelope were compared with values from controls. All four patients had evidence of epicardial RV injury at the time of pericardiectomy and persistent symptoms and RV systolic dysfunction after pericardiectomy.