Impact of Reference Mismatch on Procedure Outcomes of Percutaneous Coronary Intervention

A significant mismatch between proximal and distal reference lumen diameters of the target lesion may pose challenges during percutaneous coronary intervention (PCI) and therefore influence the outcomes. We investigated total 1706 lesions underwent IVUS guided percutaneous coronary intervention, that were divided into 2 groups, including 411 lesions in Mismatch group and 1295 lesions in Non-Mismatch group. After propensity score matching, 397 lesions in each group were selected for final data set. The analysis showed that Mismatch group PCI required more frequently use of post-stenting optimization (79.6% vs 53.9%, P < .001) using higher max pressure (19.5 ± 3.9 vs 16.7 ± 3.7 atm, P < .001). Besides, Mismatch group also encountered more PCI major complications (7.8% vs 4.0%, P = .024) and lower procedure success rate (91.4% vs 95.5%, P = .022). On final angiogram, Mismatch group had smaller minimum lumen diameter (2.62 ± .45 vs 2.90 ± .57 mm, P < .001) and lower angiographic success rate (93.2% vs 96.7%, P = .023). On final IVUS, Mismatch group had higher rate of incomplete stent apposition and stent edge dissection (6.3% vs 3.0%, P = .029 and 2.5% vs .5%, P = .021, respectively). In conclusion, reference mismatch posed significant challenging during PCI that led to unfavorable procedural outcomes. These impacts may translate into long-term clinical implications that need to be addressed in future studies.

Imaging Characteristics of Mismatch Lesions: An Angiographic and Intravascular Ultrasound Analysis of 1369 Coronary Lesions

OBJECTIVES

To evaluate the angiographic and intravascular ultrasound (IVUS) characteristics of coronary mismatch lesions.

BACKGROUND

Better understanding about the characteristics of mismatch lesions may help to achieve more accurate lesion assessment and, thereby, to improve the outcomes of percutaneous coronary intervention (PCI).

METHODS

Angiographic and IVUS data from 1369 lesions were analyzed. Mismatch lesion was defined as the difference between proximal and distal reference lumen diameters of ≥1.0 mm or ≥30% of the distal reference lumen diameter.

RESULTS

The incidence of mismatch lesions was 20.1% (275/1369). Compared to nonmismatch group, mismatch group had longer lesions (21.3 [6.4] mm vs 18.4 [6.4] mm, P < .001) with smaller minimum lumen diameter (0.87 [0.29] mm vs 1.10 [0.31] mm, P < .001) and more severe diameter stenosis (78.8% [9.2%] vs 66.3% [10.3%], P < .001). On IVUS, mismatch group had larger lumen area (18.7 [5.0] vs 15.8 [5.1] mm², P < .001) but lower plaque burden at the proximal reference segment (41.0% [9.2%] vs 45.7% [9.9%], P < .001) and smaller lumen area (4.83 [1.89] vs 7.36 [2.89] mm, P < .001) but higher plaque burden at the distal reference segment (42.9% [10.4%] vs 41.4% [10.1%], P = .023). Multivariable logistic regression analysis showed that mismatch lesions were frequently accompanied by diffuse lesions (odds ratio [OR] = 2.50; 95% confidence interval [CI]: 1.83-3.40; P < .001), bifurcation lesions (OR = 5.83; 95% CI: 4.40-7.74; P < .001), and lesions with a low TIMI flow grade (OR = 1.70; 95% CI: 1.08-2.67; P = .022) or severe diameter stenosis (OR = 3.05; 95% CI: 2.10-4.43; P < .001).

CONCLUSIONS

Mismatch lesions are quite common and characterized by greater lesion complexity compared with nonmismatch lesions. Further studies may be necessary to address the impact of this lesion type on the outcome of PCI.

The Role of Self-expanding Stents in Patients with Atypical Coronary Anatomy

Despite advances with new generation stents, there remains some atypical coronary anatomy where optimal stenting continues to be a challenge; such as stent sizing in large, ectatic or aneurysmal vessels; tapered vessels; and in vasoconstricted arteries such as in ST-segment elevation myocardial infarction or chronic total occlusions. Balloon-expandable stents are tubular and cannot easily accommodate vessel diameter variations; thrombotic vessels increase the risk of distal embolisation and no-reflow; positive remodelling and vasodilation often result in subsequent malapposition; and patients with bifurcation lesions have a higher risk of adverse events. The STENTYS BMS and DES^(P) stents have a self-expanding design, which enables a better anatomical fit to the vessel, even with diameter variations (up to 6.0 millimetres [mm]), and can adapt to changes in vessel size over time. The stents deploy atraumatically from distal to proximal, which could reduce distal embolisation and contain disconnectable bridges, which can be opened up at a side branch. Self-apposing technology could therefore provide a potential solution to current challenges with balloon-expandable stent technology.