Role of Right Ventricular Dysfunction and Diabetes Mellitus in N-terminal pro-B-type Natriuretic Peptide Response of Patients With Severe Mitral Regurgitation and Heart Failure After MitraClip

Abstract

MitraClip (MC) is an alternative therapeutic option for patients with severe mitral regurgitation (MR) who are at high surgical risk. Most candidates for MC have severe heart failure (HF) with increased N-terminal pro-B-type natriuretic peptide (NT-pro BNP) levels. We sought to clarify the response of NT-pro BNP after MC and to identify the determinants of NT-pro BNP nonresponders. Among 136 consecutive patients successfully treated with MC, we excluded 20 patients due to low baseline NT-pro BNP levels and therefore examined 116 patients. NT-pro BNP responders were defined as patients whose NT-pro BNP levels decreased by > 30% at 6 months after MC. Mean NT-pro BNP levels significantly decreased from 6,117 pg/mL at baseline to 4,143 pg/mL at 6 months after MC (P < 0.001); 61 patients (53%) were responders. Diabetes mellitus (DM) (51% versus 25%; P = 0.003) and atrial fibrillation (67% versus 49%; P = 0.049) were more common in nonresponders. Baseline New York Heart Association (NYHA) class and NT-proBNP levels were higher in responders. Right ventricular systolic dysfunction (RVSD) defined as tricuspid annular plane systolic excursion (TAPSE) < 15 mm was more common in nonresponders (41% versus 18%; P = 0.008). Multivariable logistic regression analysis revealed that DM (odds ratio [OR], 2.966; P = 0.014), RVSD (OR, 3.948; P = 0.006), and baseline NT-proBNP > 5,000 pg/mL (OR, 0.204; P = 0.001) were independent determinants of nonresponders. All-cause death tended to be less common in responders to NT-pro BNP (20% versus 31%; P = 0.163). In conclusion, NT-pro BNP levels significantly decreased after MC. DM and RVSD were determinants of NT-pro BNP nonresponse after the MC procedure.