Anatomical variations in coronary venous drainage: Challenges and solutions in delivering cardiac resynchronization therapy

Abstract

Aims To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties. Methods From four implanting institutes, data of all CRT implants between October 2008 and October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted ‘normal’ anatomy. Patient demographics, procedural detail, and subsequent left ventricle (LV) lead pacing indices were collected. Results From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2 ± 10.6 years in age with an LV ejection fraction of 34 ± 10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), five of which had coronary sinus ostium atresia (CSOA) including two with an “unroofed” coronary sinus (CS); one patient had a unique anomalous origin of the CS and one patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull‐through, including one case of endocardial LV implant. Pacing follow‐up over 37.64 ± 37.6 months demonstrated LV lead threshold between 0.62 and 2.9 volts (pulsewidth 0.4–1.5 ms) in all cases; five patients died within 2.92 ± 1.6 years of a successful implant. Conclusion CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required.

Transvenous Lead Extraction: Work in Progress

“…The femoral vein provides large, linear, direct access to the heart via the inferior vena cava and, therefore, has been used to overcome the challenging angulations associated with the subclavian access. 32 The large bore access permits the use of sizable snares safely, and the direct pathway to the heart chambers provides a geometric advantage during application of extraction forces. In a small observational study, the use of femoral snare lead extraction was found to be a successful bail-out strategy; the overall rate of clinical success and complete lead extraction was improved with the addition of femoral snare extraction after the subclavian approach had failed; without this strategy, the procedural success would have been lower than contemporary expectations.…”

Approaches for Successful Implantation of Cardiac Implantable Devices in Patients with Persistent Left Superior Vena Cava

“…There are various approaches that have been described in the literature to overcome the difficulties encountered during the placement of CS lead in a patient with PLSVC. 6 Some operators opt for implantation of the entire system via the right subclavian approach, while others implant only the LV lead via the right subclavian approach and then tunnel the lead to a left pre-pectoral pocket. Access to the CS from the RA may sometimes be challenging due to ostial stenosis, unroofed CS, and variable connections with the smooth part of the RA.…”

“…Access to the CS from the RA may sometimes be challenging due to ostial stenosis, unroofed CS, and variable connections with the smooth part of the RA. 6 Access to the CS in these situations may be facilitated by using an Amplatz Left 2 coronary catheter (Merit Medical) with a secondary curve to access the CS. In rare situations, tight angulation of the CS ostium can be navigated using 0.014-in guidewire via the PLSVC to the RA, where it can be snared from the femoral access for railroading the guide sheath into the CS to deliver the LV lead.…”

Comment on ‘Leadless Pacemakers: Current Achievements and Future Perspectives’

“…4,9 This is unfavourable compared with conventional CRT systems, which can be successfully implanted in up to 97-99% of cases (in experienced hands) on the first attempt, and in >99% of cases using unconventional methodologies with repeat procedures. [10][11][12] The CRT implantation failure rate is extremely low.…”