Morphometric Characterization of Human Coronary Veins and Subvenous Epicardial Adipose Tissue—Implications for Cardiac Resynchronization Therapy Leads

Abstract

Subvenous epicardial fat tissue (SEAT), which acts as an electrical insulation, and the venous diameter (VD) both constitute histomorphological challenges for optimal application and lead design in cardiac synchronization therapy (CRT). In this study, we characterized the morphology of human coronary veins to improve the technical design of future CRT systems and to optimize the application of CRT leads. We retrospectively analyzed data from cardiac computed tomography (CT) of 53 patients and did studies of 14 human hearts using the postmortem freeze section technique and micro CT. Morphometric parameters (tributary distances, offspring angles, luminal VD, and SEAT thickness) were assessed. The left posterior ventricular vein (VVSP) had a mean proximal VD of 4.0 ± 1.4 mm, the left marginal vein (VMS) of 3.2 ± 1.5 mm and the anterior interventricular vein (VIA) of 3.9 ± 1.3 mm. More distally (5 cm), VDs decreased to 2.4 ± 0.6 mm, 2.3 ± 0.7 mm, and 2.4 ± 0.6 mm, respectively. In their proximal portions (15 mm), veins possessed mean SEAT thicknesses of 3.2 ± 2.4 (VVSP), 3.4 ± 2.4 mm (VMS), and 4.2 ± 2.8 mm (VIA), respectively. More distally (20–70 mm), mean SEAT thicknesses decreased to alternating low levels of 1.3 ± 1.1 mm (VVSP), 1.7 ± 1.1 mm (VMS), and 4.3 ± 2.6 mm (VIA), respectively. In contrast to the VD, SEAT thicknesses alternated along the further distal vein course and did not display a continuous decrease. Besides the CRT responsiveness of different areas of the LV myocardium, SEAT is a relevant electrophysiological factor in CRT, potentially interfering with sensing and pacing. A sufficient VD is crucial for successful CRT lead placement. Measurements revealed a trend toward greater SEAT thickness for the VIA compared to VVSP and VMS, suggesting a superior signal-to-noise-ratio in VVSP and VMS.

Cardiac Computed Tomography Evaluation of Association of Left Ventricle Disfunction and Epicardial Adipose Tissue Density in Patients with Low to Intermediate Cardiovascular Risk

“…Moreover, Keiler et al [ 40 ] affirmed that Sub venous Epicardial Adipose Tissue (SEAT)—which acts as an electrical insulation—and its properties, such as density and thickness, may be relevant in prognostic evaluation of cardiac resynchronization in patients with heart failure.…”

Epicardial Adipose Tissue Measured From Computed Tomography Predicts Cardiac Resynchronization Therapy Response in Patients With Non-ischemic Systolic Heart Failure

“…Meanwhile, localized EAT accumulation around the right AV groove and left AV groove is directly related to impaired motion (30), such as, mechanical dyssynchrony, which was widely accepted corresponding to CRT response. On the other hand, EAT is a relevant electrophysiological factor in CRT patients that may interfere with pacing and sensing (7). Meanwhile, greater EAT thickness might increase under LV lead sensing and reduce battery longevity.…”

“…Previous studies (5,6) have found that EAT is a novel parameter for cardiovascular risk assessment in coronary artery disease (CAD), cardiac hypertrophy, and atrial fibrillation (AF). Moreover, a recent study also found that EAT, which plays a role as electrical insulation, could potentially interfere with sensing and pacing for lead design in CRT (7). Nevertheless, performing LV lead placement and electrode positioning according to EAT may lead to uncertainty.…”

Cardiac venous system: a literature review

“…Наименьшие вены сердца (vv. cordis minimae, Thebesian veins) дренируют интрамуральные и субэпикардиальные участки сердечной стенки, впадают непосредственно в полости камер сердца [15][16][17].…”