Prognostic value of the right coronary venous anatomy in patients undergoing cardiac resynchronization therapy
Authors: Moldovan M P , Eotvos C A , Blendea E D , Coseriu G , Burde A , Avram T , Zehan I , Sarb A , Lazar R D , Mocan L , Tentea P , Pop S , Blendea D 
Published: October 2024

Abstract

Background
The size and distribution of the coronary veins (CV) reflect both intracavitary pressure and myocardial blood flow, and therefore, in patients with cardiomyopathy, CV anatomy could potentially become a biomarker of disease severity. While the left coronary veins have been well described, there are few descriptions of the right CV system.

Purpose
Given these considerations, the aim of the study was to evaluate the anatomy of the right CV system and its potential prognostic significance in patients with advanced cardiomyopathy.

Methods
We analyzed CV angiograms from 121 patients (age 67±14 years) undergoing cardiac resynchronization therapy (CRT). The right ventricular (RV) veins were seen to fill during the injection of contrast through multiple connections with the left sided venous system. Patients were followed for a median of 43 [IQR 3-73] months, during which 12 patients expired.

Results
Anterior cardiac veins (ACV), which overlay the RV wall were observed in 85 (70%) patients and had a maximum ostial diameter of 2.04±0.8 mm. Multiple ACVs were seen in 62 patients. These veins were observed to empty directly into the venous sinus of right atrium (VSRA), into the RV, the right atrium (RA), or into the small cardiac vein (SCV) in 68, 9, 5, and 3 patients respectively. The right marginal vein (RMV) was visualized in 21 (17%) patients, had a diameter of 2.3±1.2 mm, and ran a course along the right border of the RV, emptying directly into RV, RA or into VSRA in 9, 4 and 8 patients respectively. The VSRA present in 91 (75%) patients, coursed parallel to the right coronary sulcus, collecting blood from the ACV’s and RMV’s and drained into the RA (Figure A); in 7 patients, 2 VSRA ostia were noted. VSRA lengths and diameters varied (11-119 mm, mean 41±25 mm) and (1.2-6.9mm, mean 2.7±1.2mm) respectively. The VSRA lengths correlated significantly with RV fractional area change, RV systolic pressure, tricuspid regurgitation severity evaluated by echocardiography, and P wave amplitude in ECG lead II (r=-0.65; p=0.041, r=0.88; p=0.019, r=0.52; p=0.030, and r=0.79; p=0.031 respectively). The VSRA diameters, which were significantly larger in patients with obstructive sleep apnea (3.6±1.5 vs. 2.3±1.2mm; p=0.021) correlated significantly with RV systolic pressure, and tricuspid regurgitation severity by echocardiography (r=0.77; p=0.009, and r=0.63; p=0.006 respectively). Patients who expired during follow-up had a significantly longer VSRA than patients who remained alive (Figure B). The VSRA length, RV fractional area change, and baseline QRS duration independently predicted survival in a Cox multivariate model that also included age and left ventricular ejection fraction.

Conclusions
RV venous system demonstrates a highly variable anatomy that has not been previously well described. The size of the VSRA correlated with parameters of RV function and predicted survival in patients undergoing CRT.Figure