How Left Ventricular Size Affects Severity of Disease and Long-term Prognosis in Patients with Severe Systolic Dysfunction?

Background: We compared the severity of disease, heart failure (HF) rehospitalization and trend of changes over a 12-month follow-up in clinical and biochemical measurements between dilated cardiomyopathy (DCM) patients and those with left ventricular systolic dysfunction with normal LV size (NLVS). The existing definition of DCM failed to justify our observations in some clinical circumstances resulting in diagnostic and prognostic challenges.

Methods: A total of 77 patients [52 (67.5%) male] including 40 patients in the NLVS group and 37 patients in the DCM group were enrolled and followed up for a median of 12 months [interquartile range, 11-14 months].

Results: Mean left ventricular ejection fraction was statistically comparable between NLVS and DCM patients (22 ± 8% vs. 19 ± 6%, P = 0.08]. The New York Heart Association class was statistically comparable in both groups (P = 0.23). Laboratory measurements including hemoglobin, sodium, creatinine, uric acid, and NT-proBNP level were also statistically similar in both groups (all P > 0.05). During follow-up, HF rehospitalization occurred in 16 (76%) patients in NLVS and 5 (24%) patients in DCM groups (P = 0.009). Except for left ventricular ejection fraction which improved in both NLVS and DCM groups, no significant changes were observed in clinical (New York Heart Association class) and laboratory measurements during follow-up in both NLVS and DCM groups.

Conclusions: Our study showed that NLVS defines a group of systolic HF patients which not only did not have less severe disease than those with enlarged left ventricules (i.e., DCM), also had more HF rehospitalization. These NLVS patients also had steady clinical, laboratory, and echocardiographic profile during follow-up.