Cardiac Death After Transcatheter Aortic Valve Replacement With Contemporary Devices

Prognostic Value of Microvascular Resistance Reserve Measured Immediately After PCI in Stable Coronary Artery Disease

BACKGROUND

Microvascular resistance reserve (MRR) has been proposed as a specific metric to quantify coronary microvascular function. The long-term prognostic value of MRR measured in stable patients immediately after percutaneous coronary intervention (PCI) is unknown. This study sought to determine the prognostic value of MRR measured immediately after PCI in patients with stable coronary artery disease.

METHODS

This study included 502 patients with stable coronary artery disease who underwent elective PCI and coronary physiological measurements, including pressure and flow estimation using a bolus thermodilution method after PCI. MRR was calculated as coronary flow reserve divided by fractional flow reserve times the ratio of mean aortic pressure at rest to that at maximal hyperemia induced by hyperemic agents. An abnormal MRR was defined as ≤2.5. Major adverse cardiac events (MACEs) were defined as a composite of all-cause mortality, any myocardial infarction, and target-vessel revascularization.

RESULTS

During a median follow-up of 3.4 years, the cumulative MACE rate was significantly higher in the abnormal MRR group (12.5 versus 8.3 per 100 patient-years; hazard ratio 1.53 [95% CI, 1.10-2.11]; P<0.001). A higher all-cause mortality rate primarily drove this difference. On multivariable analysis, a higher MRR value was independently associated with lower MACE and lower mortality. When comparing 4 subgroups according to MRR and the index of microcirculatory resistance, patients with both abnormal MRR and index of microcirculatory resistance (≥25) had the highest MACE rate.

CONCLUSIONS

An abnormal MRR measured immediately after PCI in patients with stable coronary artery disease is an independent predictor of MACE, particularly all-cause mortality.

Asymptomatic Aortic Stenosis: From Risk Stratification to Treatment

Our understanding of the natural history of aortic stenosis has significantly increased over the last decade. There have been considerable advances in the diagnosis and risk stratification of patients with aortic stenosis and in surgical and anesthetic techniques. In addition, transcatheter aortic valve replacement has established itself as a viable alternative to surgical management. Inevitably, these developments have raised questions regarding the merits of waiting for symptom onset in asymptomatic patients with severe aortic stenosis before offering treatment. Recent observational and randomized trial data suggest that early intervention in asymptomatic patients with severe aortic stenosis and normal left ventricular function may confer a prognostic advantage to a watchful waiting strategy. In this review, we highlight advances in the management and risk stratification of patients with asymptomatic severe aortic stenosis with particular consideration of recent findings supporting early valvular intervention.

Survival After Surgical Aortic Valve Replacement in Low-Risk Patients: A Contemporary Trial Benchmark

BACKGROUND

The use of transcatheter aortic valve replacement for severe aortic stenosis in low-risk patients necessitates an evaluation of contemporary long-term, real-world outcomes of similar patients undergoing surgical aortic valve replacement (SAVR) in a national cohort.

METHODS

All patients undergoing primary, isolated SAVR in The Society of Thoracic Surgeons (STS) database between 2011 and 2019 were examined. The study population of 42,586 adhered to the inclusion/exclusion criteria of the Placement of Aortic Transcatheter Valves (PARTNER) 3 and Evolut Low Risk randomized trials. Patients were further stratified by STS predicted risk of mortality (PROM), age, and left ventricular ejection fraction. The primary end-point was all-cause National Death Index mortality. Unadjusted survival to 8 years was estimated using the Kaplan-Meier method.

RESULTS

Mean age was 74.3 ± 5.7 years and mean STS PROM was 1.9% ± 0.8%. The overall Kaplan-Meier time to event analysis for all-cause mortality at 1, 3, 5, and 8 years was 2.6%, 4.5%, 7.1%, and 12.4%, respectively. In subset analyses, survival was significantly better for (1) lower STS PROM (P < .001), (2) younger vs older age (P < .001), and (3) higher vs lower left ventricular ejection fraction (P < .001). When STS PROM was below 1% or the patient age was below age 75 years, the 8-year survival after SAVR was 95%.

CONCLUSIONS

The results of this national study confirm that long-term survival after SAVR remains excellent, at 92.9% at 5 years. These contemporary longitudinal data serve to aid in the balanced interpretation of current and future trials comparing SAVR and transcatheter aortic valve replacement and may assist in the clinical decision-making process for patients of lower surgical risk.