Surgical aortic valve replacement etiologies, hemodynamics, and outcomes in 1346 patients from the Malaysian heart centre

Abstract

Background: This study examined the characteristics and outcomes of surgical aortic valve replacement (SAVR) both isolated and in combination with other cardiac surgery in Malaysia from 2015 to 2021.

Methods: This was a retrospective study of 1346 patients analyzed on the basis of medical records, echocardiograms and surgical reports. The overall sample was both considered as a whole and divided into aortic stenosis (AS)/aortic regurgitation (AR)-predominant and similar-severity subgroups.

Results: The most common diagnosis was severe AS (34.6%), with the 3 most common etiologies being bicuspid valve degeneration (45.3%), trileaflet valve degeneration (36.3%) and rheumatic valve disease (12.2%). The second most common diagnosis was severe AR (25.5%), with the most common etiologies being root dilatation (21.0%), infective endocarditis (IE) (16.6%) and fused prolapse (12.2%). Rheumatic valve disease was the most common mixed disease. A total of 54.5% had AS-predominant pathology (3 most common etiologies: bicuspid valve degeneration valve, degenerative trileaflet valve and rheumatic valve disease), 36.9% had AR-predominant pathology (top etiologies: root dilatation, rheumatic valve disease and IE), and 8.6% had similar severity of AS and AR. Overall, 62.9% of patients had trileaflet valve morphology, 33.3% bicuspid, 0.6% unicuspid and 0.3% quadricuspid. For AS, the majority were high-gradient severe AS (49.9%), followed by normal-flow low-gradient (LG) severe AS (10.0%), paradoxical low-flow (LF)-LG severe AS (6.4%) and classical LF-LG severe AS (6.1%). The overall in-hospital and total 1-year mortality rates were 6.4% and 14.8%, respectively. Pure severe AS had the highest mortality. For AS-predominant pathology, the etiology with the highest mortality was trileaflet valve degeneration; for AR-predominant pathology, it was dissection. The overall survival probability at 5 years was 79.5% in all patients, 75.7% in the AS-predominant subgroup, 83.3% in the AR-predominant subgroup, and 87.3% in the similar-severity subgroup.

Conclusions: The 3 most common causes of AS- predominant patients undergoing SAVR is bicuspid valve degeneration, degenerative trileaflet valve and rheumatic and for AR-predominant is root dilatation, rheumatic and IE. Rheumatic valve disease is an important etiology in our SAVR patients especially in mixed aortic valve disease. Study registration IJNREC/562/2022.

Keywords: Aortic valve; Echocardiography; Etiology; Low gradient; Prosthesis.

Fig. 1

Flow chart in total, there were 1503 patients who underwent SAVR at IJN from 2016 to 2021. A total of 157 patients were excluded, and the other 1346 were analyzed. These patients were considered overall and subdivided into AS-predominant vs. AR-predominant vs. similar-severity subgroups

Fig. 2

AS-predominant vs. AR-predominant vs. similar severity pathology. AS predominant was the most common pathology, followed by AR predominant and then similar severity

Fig. 3

a Leaflet morphology. Leaflet morphology ascertained from TEE and/or surgical reports. The most common morphology was trileaflet (62.9%), followed by bicuspid (33.3%), unicuspid (0.6%) and quadricuspid (0.3%). In 2.9% of patients, the number of leaflets could not be determined. b AS classification, N = 974 Hemodynamics (gradient, flow and severity) for patients with any degree of AS. The most common category was HG-severe AS (49.9%), and the least common was reverse area-gradient mismatch (2.7%)

Fig. 4

a Kaplan‒Meier curves for patients overall For all SAVR patients, the probability of survival at 5 years was 79.5%. b Kaplan‒Meier curves for the AS-predominant, AR-predominant, and similar-severity groups. For the AS-predominant group, the probability of 5-year survival was 75.7%; for the AR-predominant group, it was 83.3%; and for the similar-severity group, it was 87.3%