Severely Reduced Left Ventricular Function may Not Significantly Increase In-Hospital Mortality During Complex Cardiac Procedures: Study

These findings are published in the Indian Heart Journal in April 2025.

The Clinical Challenges of Calcified Coronary Lesions

Severe coronary arterial calcification is present in approximately 25% of patients requiring Percutaneous Coronary Intervention (PCI), a nonsurgical procedure used to open blocked heart arteries. These lesions are difficult to treat because they hinder proper stent delivery and expansion, increasing the risk of stent thrombosis or restenosis. Rotational atherectomy (RA) utilizes a high-speed diamond-crystal burr to debulk and modify these calcific plaques. However, the process creates micro-debris that can wash downstream, causing microvascular obstruction and temporary heart muscle "stunning." Historically, this led manufacturers to consider a severely reduced left ventricular (LV) systolic function—the heart's ability to pump blood—as a relative contraindication for the procedure due to fears of exaggerated adverse effects.

Study Overview

The retrospective, single-center review was conducted at the U. N. Mehta Institute of Cardiology and Research Centre (UNMICRC), a tertiary care facility in India. The study analyzed 504 consecutive patients who underwent RA-assisted PCI between February 2018 and March 2023. Patients were divided into two groups: Group 1 consisted of 209 patients with a severely reduced LVEF of 35% or less, while Group 2 included 295 patients with a moderately reduced or preserved LVEF of more than 35%. The researchers recorded procedural details, demographic risk factors, and in-hospital outcomes, with the primary endpoint being in-hospital mortality.

The key findings from the study include

• Among the 504 patients, the overall in-hospital mortality rate was low at 1.4% (7 patients).

• The incidence of mortality did not differ significantly between groups, with 2.3% in the low LVEF group versus 0.7% in the preserved LVEF group.

• The study found that LVEF was not an independent predictor of in-hospital mortality after adjusting for other risk factors.

• Procedural success, defined by successful revascularization and Thrombolysis in Myocardial Infarction (TIMI) grade III flow, was high and similar across both groups.

Clinical Relevance and Future Directions

For practicing physicians, the study—the largest of its kind to date—demonstrates that RA can be performed safely in high-risk patients with severely reduced LVEF (≤35%) without an increase in short-term mortality. The lack of significant difference suggests that modern techniques, such as using smaller burrs and lower rotational speeds, help minimize vascular injury and microvascular complications. However, clinicians should note the study's focus on in-hospital outcomes; the long-term effects of heart function on mortality may become more pronounced over time. While RA appears safe in the short term for this cohort, the low number of total events and the limited use of intra-vascular imaging (6.7%) suggest a need for larger, prospective meta-analyses to confirm these results and optimize patient selection in complex calcific cases.

Reference

Kanabar K, Vyas P, Patel K, Behra G. Short-term outcomes of rotational atherectomy in patients with reduced left ventricular ejection fraction: A retrospective review from a tertiary referral centre. Indian Heart Journal. 2025 April 2; 77:170–173