The Registry Evaluating Functional Outcomes of Resynchronization Management (REFORM): quality of life and psychological functioning in patients receiving cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) is a treatment for heart failure (HF) that improves cardiac, functional, and quality of life (QoL) outcomes. This study was designed to examine the effect of the addition of CRT (CRTD) to the implantable cardioverter defibrillator (ICD) on psychological functioning. METHODS AND RESULTS: Overall, 99 participants completed batteries before and 9 months after ICD or CRTD implantation in a registry of HF patients receiving device treatment in 3 US centers. Measures included validated indices of mental health (State Trait Anxiety Inventory, Patient Health Questionnaire: Depression) and generic and disease/device-specific QoL (Medical Outcomes Study-Short Form-12, Kansas City Cardiomyopathy Questionnaire, Florida Patient Acceptance Survey, Florida Shock Anxiety Scale). Mixed between-within analyses of covariance were employed to compare device groups on each outcome controlling for cardiac and demographic covariates. Clinically significant anxiety was elevated in both groups at both time points (57% CRTD at baseline, 29% CRTD 9 months, 44% ICD at baseline, 45% ICD 9 months). Clinically significant depressive symptoms were high at baseline (38% CRTD, 31% ICD), but dropped at follow-up (16% CRTD, 7% ICD; P = 0.01). Participants with CRTD had improved mental component and disease-specific QoL following CRT; however, CRTD patients had worse QoL, worse mental component QoL at baseline, and worse device acceptance at 9-month follow-up than patients with ICDs (all P < 0.05). CONCLUSIONS: Evidence of low QoL, psychological functioning, and device acceptance provides the impetus to increase research on well-being of HF patients being implanted with CRTD in research and clinical work.

Do baseline diastolic echocardiographic parameters predict outcome after resynchronization therapy? Results from the PROSPECT trial.

INTRODUCTION: Cardiac resynchronization therapy (CRT) can improve clinical and cardiac structural status in heart failure patients. The role of baseline diastolic echocardiographic parameters to characterize the likelihood of positive outcomes is not well known. We explored relationships between diastolic parameters and outcomes 6 months after CRT implant in the Predictors of Response to CRT (PROSPECT) Trial. HYPOTHESIS: We hypothesized that diastolic echocardiographic parameters were associated with clinical and structural outcomes in CRT patients. METHODS: For 426 patients in PROSPECT, a prospective observational trial of CRT, baseline E/A ratio, left atrial (LA) area, isovolumic relaxation time, left ventricular inflow deceleration time, E' velocity, and E/E' ratio were evaluated and related to 6-month clinical composite score (CCS) and left ventricular end-systolic volume (LVESV) reduction using Spearman rank-order correlations. Parameters associated with outcomes were analyzed further by discrete categorization. RESULTS: As continuous variables, only E/A ratio and LA area correlated with CCSs (P = 0.017, P = 0.045, respectively) and relative change in LVESV at 6 months (P < 0.0001, P = 0.001, respectively). As discrete variables, E/A ratio and LA area also correlated with CCSs and LVESV. CONCLUSION: Diastolic echo parameters E/A ratio and LA area were associated with clinical and structural outcomes in CRT patients at 6 months.

Predictors of response to cardiac resynchronization therapy (PROSPECT)--study design.

BACKGROUND: Cardiac resynchronization therapy (CRT) is currently indicated in patients with moderate to severe heart failure, a wide QRS complex and significant left ventricular dysfunction despite optimal medical therapy. Adoption of these criteria for CRT results in a favorable response in only two thirds of candidates. METHODS: "Predictors of response to cardiac resynchronization therapy (PROSPECT)," a prospective, multicenter, nonrandomized study, aims to identify echocardiographic measures of dyssynchrony and evaluate their ability to predict response to CRT. PROSPECT will enroll approximately 300 patients in up to 75 centers in the United States, Asia, and Europe with clinical follow-up for 6 months. We will prospectively and individually test a variety of conventional echocardiographic and tissue Doppler imaging parameters against measures of clinical response. The primary response criteria are improvement in the heart failure Clinical Composite Score and left ventricular reverse remodeling. Enrollment began in March 2004 and is expected to conclude early 2005.

The effects of displacement rate and proteoglycan digestion on the fracture resistance of tissue grown from chondrocyte culture.

Fracture toughness of cartilage and cartilage replacement tissues is important in injury and disease. For example, cartilage is thought to weaken before it fibrillates in the disease osteoarthritis. Since both loading rate and proteoglycan content affect viscoelastic properties, they may both affect fracture toughness of cartilage and cartilage analogs. In this study, fracture toughness of tissue grown in chondrocyte culture was measured as a function of loading rate and proteoglycan digestion. Control tissue and tissue digested with chondroitinase ABC (cABC) to remove proteoglycans were tested at displacement rates of 0.1 and 0.5 mm/sec. Displacement rate had no effect on fracture toughness for either control or digested tissue. Proteoglycan digestion reduced tissue thickness by 30% and when evaluated on a material basis increased fracture toughness. There was no interaction between digestion and loading rate. When the fracture toughness was normalized to collagen content, which removed the effect of tissue shrinkage, there was no effect of proteoglycan digestion on fracture toughness. These data suggest that proteoglycans do not contribute to tissue toughness, other than by reducing thickness and increasing collagen density.