Percutaneous management of coronary bifurcation lesions: current perspective.

PURPOSE OF REVIEW: Coronary artery disease affecting bifurcations poses a challenge for percutaneous intervention. Several techniques and strategies for percutaneous management of bifurcation lesions have been described in the literature with variable data available for outcomes. In this review, we provide an overview of the strategies and techniques used for percutaneous intervention of bifurcation lesions with an update of recent technical developments and clinical evidence. RECENT FINDINGS: The coronary bifurcation lesions of both left main and other coronary segments are best treated with a provisional stenting strategy where main branch is treated with a stent placement and side branch intervention reserved for angiographically or physiologically determined hemodynamically significant residual stenosis despite application of a proximal stent optimization technique. When a provisional stent strategy is not likely to be successful due to anatomic or morphologic lesion characteristics and a large side branch or distal left main bifurcation is involved, an upfront bifurcation stenting strategy with double kissing crush technique may provide the optimum results. Coronary imaging and fractional flow determination may guide lesion specific management, facilitate device selection and improve clinical outcomes for percutaneous therapy for bifurcation lesions. SUMMARY: Despite advances in technology and procedural techniques, percutaneous intervention of coronary bifurcation lesions remains challenging and associated with higher adverse outcomes compared to non bifurcation lesions. Among the several bifurcation strategies, a provisional stenting approach is preferred for technical simplicity and better long term outcomes. Double kissing crush technique provides superior clinical results and should be preferred when a two stent strategy is indicated. Use of coronary imaging and physiology assessment should be incorporated in the algorithm of bifurcation interventions for greater technical and clinical success.

The Learning Curve and Annual Procedure Volume Standards for Optimum Outcomes of Transcatheter Aortic Valve Replacement: Findings From an International Registry.

OBJECTIVES: The authors aimed to determine the procedural learning curve and minimum annual institutional volumes associated with optimum clinical outcomes for transcatheter aortic valve replacement (TAVR). BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a complex procedure requiring significant training and experience for successful outcome. Despite increasing use of TAVR across institutions, limited information is available for its learning curve characteristics and minimum annual volumes required to optimize clinical outcomes. METHODS: The study collected data for patients at 16 centers participating in the international TAVR registry since initiation of the respective TAVR program. All cases were chronologically ordered into initial (1 to 75), early (76 to 150), intermediate (151 to 225), high (226 to 300), and very high (>300) experience operators for TAVR learning curve characterization. In addition, participating institutions were stratified by annual TAVR case volume into low-volume (<50), moderate-volume (50 to 100), and high-volume (>100) groups for comparative analysis. Procedural and 30-day clinical outcomes were collected and multivariate regression analysis performed for 30-day mortality and the early safety endpoint. RESULTS: A total of 3,403 patients comprised the study population. On multivariate analysis, all-cause mortality was significantly higher for initial (odds ratio [OR]: 3.83; 95% confidence interval [CI]: 1.93 to 7.60), early (OR: 2.41; 95% CI: 1.51 to 5.03), and intermediate (OR: 2.53; 95% CI: 1.19 to 5.40) experience groups compared with the very high experience operators. In addition, the early safety endpoint was significantly worse for all experience groups compared with the very high experience operators. Low annual volume (<50) TAVR institutions had significantly higher all-cause 30-day mortality (OR: 2.70; 95% CI: 1.44 to 5.07) and worse early safety endpoint (OR: 1.60; 95% CI: 1.17 to 2.17) compared with the moderate- and high-volume groups. There was no difference in patient outcomes between intermediate and high annual volume groups. CONCLUSIONS: TAVR procedures display important learning curve characteristics with both greater procedural safety and a lower mortality when performed by experienced operators. In addition, TAVR performed at low annual volume (<50 procedures) institutions is associated with decreased procedural safety and higher patient mortality. These findings have important implications for operator training and patient care at centers performing TAVR.

The Learning Curve and Annual Procedure Volume Standards for Optimum Outcomes of Transcatheter Aortic Valve Replacement: Findings From an International Registry

OBJECTIVES: The authors aimed to determine the procedural learning curve and minimum annual institutional volumes associated with optimum clinical outcomes for transcatheter aortic valve replacement (TAVR).BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a complex procedure requiring significant training and experience for successful outcome. Despite increasing use of TAVR across institutions, limited information is available for its learning curve characteristics and minimum annual volumes required to optimize clinical outcomes. METHODS: The study collected data for patients at 16 centers participating in the international TAVR registry since initiation of the respective TAVR program. All cases were chronologically ordered into initial (1 to 75), early (76 to 150), intermediate (151 to 225), high (226 to 300), and very high (>300) experience operators for TAVR learning curve characterization. In addition, participating institutions were stratified by annual TAVR case volume into low-volume (<50), moderate-volume (50 to 100), and high-volume (>100) groups for comparative analysis. Procedural and 30-day clinical outcomes were collected and multivariate regression analysis performed for 30-day mortality and the early safety endpoint. RESULTS: A total of 3,403 patients comprised the study population. On multivariate analysis, all-cause mortality was significantly higher for initial (odds ratio [OR]: 3.83; 95% confidence interval [CI]: 1.93 to 7.60), early (OR: 2.41; 95%CI: 1.51 to 5.03), and intermediate (OR: 2.53; 95% CI: 1.19 to 5.40) experience groups compared with the very high experience operators. In addition, the early safety endpoint was significantly worse for all experience groups compared with the very high experience operators. Low annual volume (<50) TAVR institutions had significantly higher all-cause30-day mortality (OR: 2.70; 95% CI: 1.44 to 5.07) and worse early safety endpoint (OR: 1.60; 95% CI: 1.17 to 2.17) compared with the moderate- and high-volume groups. There was no difference in patient outcomes between intermediate and high annual volume groups. CONCLUSIONS: TAVR procedures display important learning curve characteristics with both greater procedural safety and a lower mortality when performed by experienced operators. In addition, TAVR performed at low annual volume (<50 procedures) institutions is associated with decreased procedural safety and higher patient mortality. These findings have important implications for operator training and patient care at centers performing TAVR.

Institutional experience and outcomes of transcatheter aortic valve replacement: Results from an international multicentre registry.

BACKGROUND: Despite rapidly increasing use of TAVR across institutions, limited data is available for the effect of procedural experience on TAVR outcomes. We investigate the relationship between institutional experience and TAVR outcomes. METHODS: 1953 patients undergoing TAVR at 8 international sites were grouped into chronological quantiles (Q) to assess temporal changes on procedural and clinical outcomes and multivariate logistic regression performed to determine predictors of device success, early safety and all-cause mortality. RESULTS: The mean age of patients was 81±7years and 991 (51%) were female. The quantiles comprised of first 62 cases for Q1, 63-133 for Q2, 134 to 242 for Q3 and 243 to 476 for Q4. Device success increased from Q1 to Q4 (78% vs 89%, p<0.001) with significant improvement in the early safety endpoint (19% vs 10%, p<0.001). All cause mortality reduced by half in Q4 compared to Q1 (8% vs 4%, p=0.01) and rates of major vascular complications, major bleeding and valve embolization decreased with increasing experience. The multivariate analysis identified TAVR in Q3 and Q4 to be independently associated with higher device success and lower risk of complications. TAVR in Q4 was independently associated with lower mortality (OR 0.36 95% CI 0.19-0.70, p=0.002). CONCLUSIONS: Greater institutional experience with TAVR procedures improves device success and clinical outcomes. An experience of >242 cases is independently associated with lower mortality. These findings have important implications for defining minimum volume criteria for institutions and training standards for TAVR procedure.

Transcatheter Tricuspid Repair With MitraClip for Severe Primary Tricuspid Regurgitation.

Severe tricuspid regurgitation is an independent predictor of adverse outcomes, yet few patients undergo surgery and treatment with medical therapy is often inadequate. Recent studies have reported the use of the MitraClip system (Abbott Vascular) to treat secondary tricuspid regurgitation. We describe the first use of MitraClip to treat severe primary tricuspid regurgitation and right heart failure in a patient with previous cardiac transplantation and high surgical risk.

Short Duration vs Standard Duration of Dual-Antiplatelet Therapy After Percutaneous Coronary Intervention With Second-Generation Drug-Eluting Stents - A Systematic Review, Meta-Analysis, and Meta-Regression Analysis of Randomized Controlled Trials.

BACKGROUND: Current guidelines recommend 12 months of dual-antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation. Whether the duration of DAPT can be safely shortened with use of second-generation DESs is unclear. METHODS: We conducted a meta-analysis of randomized controlled trials comparing short duration (SD) (3-6 months) with standard longer duration (LD) (≥12 months) DAPT in patients treated with primarily second-generation DES implantation. Meta-regression was performed to explore the relationship between acute coronary syndrome (ACS) and the effect of DAPT duration. RESULTS: Six studies were included, with 12,752/13,928 (91.5%) patients receiving second-generation DESs. A total of 5367 patients (39%) had PCI in the setting of ACS. There was no difference in all-cause mortality (1.1% vs 1.2%; odds ratio [OR], 0.86; 95% confidence interval [CI], 0.63-1.18; P=.36) or cardiac mortality (0.9% vs 1.0%; OR, 0.92; 95% CI, 0.61-1.39; P=.69) with SD-DAPT vs LD-DAPT, respectively. Definite/probable stent thrombosis (0.5% vs 0.3%; OR, 1.33; 95% CI, 0.75-2.34; P=.51), myocardial infarction (1.5% vs 1.3%; OR, 1.17; 95% CI, 0.88-1.56; P=.29), and stroke (0.4% vs 0.4%; OR, 1.04; 95% CI, 0.60-1.81; P=.88) were similar between the groups. Compared with LD-DAPT, SD-DAPT was associated with lower clinically significant bleeding (0.9% vs 1.4%; OR, 0.64; 95% CI, 0.46-0.89; P=.01). Meta-regression analysis showed no significant association between the proportion of ACS patients in trials and duration of DAPT for the outcomes of mortality (P=.95), myocardial infarction (P=.98), or stent thrombosis (P=.89). CONCLUSION: In low-risk patients treated with contemporary second-generation DES implantation, SD-DAPT has similar rates of mortality, myocardial infarction, and stent thrombosis, with lower rates of bleeding compared with LD-DAPT.

Radiation dose reduction in the cardiac catheterization laboratory utilizing a novel protocol.

OBJECTIVES: This study reports the results a novel radiation reduction protocol (RRP) system for coronary angiography and interventional procedures and the determinants of radiation dose. BACKGROUND: The cardiac catheterization laboratory is an important source of radiation and should be kept in good working order with dose-reduction and monitoring capabilities. METHODS: All diagnostic coronary angiograms and percutaneous coronary interventions from a single catheterization laboratory were analyzed 2 months before and after RRP implementation. The primary outcome was the relative dose reduction at the interventional reference point. Separate analyses were done for conventional 15 frames/s (FPS) and at reduced 7.5 FPS post-RRP groups. RESULTS: A total of 605 patients underwent coronary angiography (309 before RRP and 296 after RRP), with 129 (42%) and 122 (41%) undergoing percutaneous coronary interventions before and after RRP, respectively. With RRP, a 48% dose reduction (1.07 ± 0.05 Gy vs. 0.56 ± 0.03 Gy, p < 0.0001) was obtained, 35% with 15 FPS RRP (0.70 ± 0.05 Gy, p < 0.0001) and 62% with 7.5 FPS RRP (0.41 ± 0.03 Gy, p < 0.001). Similar dose reductions for diagnostic angiograms and percutaneous coronary interventions were noted. There was no change in the number of stents placed or vessels intervened on. Increased dose was associated with male sex, radial approach, increasing body mass index, cine runs, and frame rates. Using a multivariable model, a 48% relative risk with RRP (p < 0.001), 44% with 15 FPS RRP and 68% with 7.5 FPS RRP was obtained. CONCLUSIONS: We demonstrate a highly significant 48.5% adjusted radiation dose reduction using a novel algorithm, which needs strong consideration among interventional cardiology practice.

An unusual cause of ventricular tachycardia: Port-A-Cath fracture and embolization into the pulmonary artery.

We describe the case of a patient with a previously placed Port-A-Cath who was admitted to hospital for new onset of non-flushing catheter and palpitations with ventricular tachycardia. A chest X-ray and a linogram showed a Port-A-Cath fracture and distal embolization into the right ventricle resulting in ventricular tachycardia. The catheter was removed percutaneously using a Goose Neck snare with no complications and resolution of the ventricular tachycardia. The removed segment demonstrated thrombus. Prompt removal of the embolized catheter fragments should be undertaken given the subtle nature of the embolization and the potential complications.