P49 THE IMPACT OF MITRAL VALVE SURGERY ON VENTRICULAR ARRHYTHMIAS IN PATIENTS WITH BARLOW’S DISEASE: PRELIMINARY RESULTS OF A PROSPECTIVE STUDY

Abstract

Abstract Background Barlow’s disease is associated with malignant ventricular arrhythmias (VA) and sudden cardiac death. No definitive data are available on baseline arrhythmic burden and evolution of VA in pts undergoing mitral surgery for concomitant severe mitral regurgitation (MR), therefore we started a prospective, single–center study with these two aims. Materials & Methods From February 2021 to May 2022, 88 consecutive pts with severe MR and Barlow’s disease were admitted to our Institution for surgical treatment of MR and were prospectively enrolled in this study. All pts underwent 24–hour Holter monitoring before surgery. A subgroup of them (16 pts, 18.2%) also had either cardiac MRI or CT scan, to detect myocardial fibrosis. Sixty–three mitral repair pts completed 3 months echocardiographic and Holter follow–up. Significant arrhythmic burden was defined as >= 1% premature ventricular beats (PVB)/24 h or at least one episode of non sustained ventricular tachycardia (NSVT), ventricular tachycardia (VT) or ventricular fibrillation (VF). Preoperative, intra and postoperative variables were compared between arrhythmogenic (AR) and non–arrhythmogenic (NAR) pts. Results At baseline (88 patients): • 29 patients (33%) had significant arrhythmic burden (median 2000 PVB/24h) and 59 did not (67%, median 24 PVB/24h) • AR pts tended to be more often females with history of palpitations. Changes in VA were assessed in 63 mitral repair pts who completed 3 months follow–up. Among them, those with significant arrhythmic burden at baseline (20 pts) did not show significant VA at follow–up in 55 % of cases, while pts without relevant VA at baseline remained free from them in 81.4% of cases and worsened in 18.6% (8 pts). Conclusions In our experience, 1/3 of Barlow’s pts with severe MR, referred for mitral surgery, showed a significant arrhythmic burden.These pts more frequently experienced palpitations and were affected by polymorphic PVB, but no other differences were found in clinical or echocardiographic characteristics (including MAD prevalence) between AR and NAR subjects. Almost half of pts with arrhythmic burden at baseline were free from significant VA after mitral repair. However, a minority (18.6%) of subjects without arrhythmic burden at baseline experienced a significant PVB burden at follow–up. Our prospective study will continue to enroll pts to investigate in a larger sample with longer follow–up the role of MV repair on VA.