In patients undergoing cardiac resynchronization therapy, those with ischemic cardiomyopathy exhibited significantly higher phase standard deviation (40.58 vs 29.77) than non-ischemic patients.
Observational (n=55)
No
Are phase standard deviation and histogram bandwidth derived from Heart Function View software associated with clinical characteristics and ventricular volumes in patients undergoing cardiac resynchronization therapy?
Phase analysis using Heart Function View software reveals that patients with ischemic cardiomyopathy exhibit significantly greater mechanical dyssynchrony post-CRT compared to those with non-ischemic cardiomyopathy.
Absolute Event Rate: 40.58% vs 29.77%
p-value: p=0.019
Background: Response to cardiac resynchronization therapy (CRT) in patients with mechanical dyssynchrony shows that echocardiographic indices alone poorly predict outcomes, highlighting the need for alternative markers. Phase standard deviation (PhSD) and histogram bandwidth (PhHB), used in the “Heart Function View (HFV) ” software, are effective left ventricle dyssynchrony indicators. Therefore, we assessed clinical characteristics associated with PhSD and PhHB from HFV and evaluated the utility of phase analysis in CRT patients. Methods: Patients underwent quantitative-gated myocardial perfusion single-photon emission computed tomography with 99m Tc-tetrofosmin. Data were stratified by sex, age, and presence/absence of ischemic heart disease. Results: Fifty-five patients were included. Primary CRT indications were heart failure with reduced ejection fraction (HFrEF), atrioventricular (AV) block, and sick sinus syndrome. Most patients had non-ischemic cardiomyopathy, with significant differences in phase analysis between patients with ischemic and non-ischemic cardiomyopathy. QRS duration demonstrated a significant reduction following CRT implementation. A strong positive correlation was observed between PhSD and PhHB. Multiple linear regression models revealed that functional parameters significantly predicted both PhSD and PhHB, with end-diastolic volume having the strongest standardized effect in both models. Furthermore, patients with HFrEF exhibited the highest and largest PhSD values and ventricular volumes, respectively, whereas patients with AV block had the highest ejection fraction. Conclusions: PhSD and PhHB were strongly positively correlated among patients who had undergone CRT. Evaluating phase parameters based on a history of ischemic heart disease and other coronary indications, rather than age or sex, may be essential for optimizing CRT outcomes.
Tomioka et al. (Thu,) conducted a observational in Heart failure requiring Cardiac Resynchronization Therapy (n=55). Ischemic cardiomyopathy vs. Non-ischemic cardiomyopathy was evaluated on Phase standard deviation (PhSD) (p=0.019). In patients undergoing cardiac resynchronization therapy, those with ischemic cardiomyopathy exhibited significantly higher phase standard deviation (40.58 vs 29.77) than non-ischemic patients.