Length-to-diameter ratio predicts target lesion revascularization in patients undergoing percutaneous coronary intervention

Background

The introduction of drug-eluting stents (DES) has substantially improved safety and outcome after percutaneous coronary intervention (PCI), resulting in lower rates of procedure related complications such as target lesion revascularization (TLR) and stent thrombosis (ST). Previous studies have demonstrated associations between TLR and various stent-related characteristics, however, the prognostic performance of these individual parameters remains modest.

Purpose

This study evaluates the predictive performance of basic stent characteristics and introduces a novel length-to-diameter ratio (L/D-Ratio) as a composite metric for the prediction of TLR.

Methods

Patients who underwent PCI with second-generation DES implantation between 2010 and 2021 at a tertiary care centre were included in this study. L/D-Ratio was defined as the quotient of maximal stent length and minimal stent diameter. The primary endpoint was defined as TLR within a year after the index procedure and the secondary endpoint as 30-day ST.

Results

The total study population comprised of 11910 patients with a median age of 65 (IQR: 55-75) years and 73.8% (n = 8790) of patients being male. Within one year, TLR occurred in 589 (4.9 %) patients. These patients more frequently underwent elective index PCI (p < 0.001) and had a higher prevalence of hypertension, hyperlipidemia, diabetes and chronic kidney disease (p for all < 0.001). Compared to patients without, those with TLR showed significantly higher mortality rates (p = 0.024).

Patients with TLR had a higher L/D-Ratio (7.5 vs. 7.2, p = 0.001), greater maximal stent length (23 vs. 22 mm, p = 0.007), greater total stent length (38.00 vs. 30.00 mm, p < 0.001) and higher number of stents (2 vs. 1, p < 0.001) than the ones without. Patients with a higher L/D-Ratio showed increased rates of TLR (log-rank p < 0.001). In multivariable regression analysis for various clinical and interventional variables the L/D-Ratio demonstrated the strongest association with TLR (HR per 1-SD 1.15 [CI: 1.06 - 1.24], p < 0.001). Receiver operating characteristic (ROC) demonstrated superior discriminatory performance of the L/D-Ratio for TLR compared to stent diameter (AUC 0.539 vs. 0.465, p = 0.001) and comparable discriminatory performance to maximal stent length (AUC 0.539 vs. 0.533, p = 0.139). In secondary analysis, 30-day ST occurred in a total of 35 patients (0.29 %). Patients with higher L/D-Ratios had increased rates of ST (log-rank p = 0.002). In multivariable logistic regression only L/D-Ratio (adj. HR per 1-SD 1.41 [1.04 – 1.91], p = 0.026) and stent length (adj. HR per 1-SD 1.40 [1.01 – 1.92], p = 0.042) were associated with a higher risk of 30-day ST.

Conclusion

The L/D-Ratio is a suitable predictor of 1-year TLR and 30-day ST after second-generation DES implantation. Its predictive value seems to be mainly driven by stent length rather than diameter, highlighting the importance of optimal stent sizing.KM-Curves TLR and STFor image description, please refer to the figure legend and surrounding text.HR-Plot TLR and STFor image description, please refer to the figure legend and surrounding text.