Preventing Coronary Obstruction During Transcatheter Aortic Valve Replacement: Results From the Multicenter International BASILICA Registry.

OBJECTIVES: This study sought to determine the safety of the BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction) procedure. BACKGROUND: Transcatheter aortic valve replacement causes coronary artery obstruction in 0.7% of cases, with 40% to 50% mortality. BASILICA is a procedure to prevent coronary obstruction. Safety and feasibility in a large patient cohort is lacking. METHODS: The international BASILICA registry was a retrospective, multicenter, real-world registry of patients at risk of coronary artery obstruction undergoing BASILICA and transcatheter aortic valve replacement. Valve Academic Research Consortium-2 definitions were used to adjudicate events. RESULTS: Between June 2017 and December 2020, 214 patients were included from 25 centers in North America and Europe; 72.8% had bioprosthetic aortic valves and 78.5% underwent solo BASILICA. Leaflet traversal was successful in 94.9% and leaflet laceration in 94.4%. Partial or complete coronary artery obstruction was seen in 4.7%. Procedure success, defined as successful BASILICA traversal and laceration without mortality, coronary obstruction, or emergency intervention, was achieved in 86.9%. Thirty-day mortality was 2.8% and stroke was 2.8%, with 0.5% disabling stroke. Thirty-day death and disabling stroke were seen in 3.4%. Valve Academic Research Consortium-2 composite safety was achieved in 82.8%. One-year survival was 83.9%. Outcomes were similar between solo and doppio BASILICA, between native and bioprosthetic valves, and with the use of cerebral embolic protection. CONCLUSIONS: BASILICA is safe, with low reported rates of stroke and death. BASILICA is feasible in the real-world setting, with a high procedure success rate and low rates of coronary artery obstruction.

The Fate of Transcaval Access Tracts: 12-Month Results of the Prospective NHLBI Transcaval Transcatheter Aortic Valve Replacement Study.

OBJECTIVES: The authors investigated 1-year outcomes after transcaval access and closure for transcatheter aortic valve replacement (TAVR), using commercially available nitinol cardiac occluders off-label. BACKGROUND: Transcaval access is a fully percutaneous nonfemoral artery route for TAVR. The intermediate-term fate of transcaval access tracts is not known. METHODS: The authors performed a prospective, multicenter, independently adjudicated trial of transcaval access, using Amplatzer nitinol cardiac occluders (Abbott Vascular, Minneapolis, Minnesota), among subjects without traditional transthoracic (transapical or transaortic) access options. One-year clinical follow-up included core laboratory analysis of serial abdominal computed tomography (CT). RESULTS: 100 subjects were enrolled. Twelve-month mortality was 29%. After discharge, there were no vascular complications of transcaval access. Among 83 evaluable CT scans after 12 months, 77 of fistulas (93%) were proven occluded, and only 1 was proven patent. Fistula patency was not associated with overall survival (p = 0.37), nor with heart failure admissions (15% if patent vs. 23% if occluded; p = 0.30). There were no cases of occluder fracture or migration or visceral injury. CONCLUSIONS: Results are reassuring 1 year after transcaval TAVR and closure using permeable nitinol occluders off-label. There were no late major vascular complications. CT demonstrated spontaneous closure of almost all fistulas. Results may be different in a lower-risk cohort, with increased operator experience, and using a dedicated transcaval closure device. (Transcaval Access for Transcatheter Aortic Valve Replacement in People With No Good Options for Aortic Access; NCT02280824).

Transcaval Access and Closure for Transcatheter Aortic Valve Replacement: A Prospective Investigation.

BACKGROUND: Transcaval access may enable fully percutaneous transcatheter aortic valve replacement (TAVR) without the hazards and discomfort of transthoracic (transapical or transaortic) access. OBJECTIVES: The authors performed a prospective, independently adjudicated, multicenter, single-arm trial of transcaval access for TAVR in patients who were ineligible for femoral artery access and had high or prohibitive risk of complications from transthoracic access. METHODS: A total of 100 patients underwent attempted percutaneous transcaval access to the abdominal aorta by electrifying a caval guidewire and advancing it into a pre-positioned aortic snare. After exchanging for a rigid guidewire, conventional TAVR was performed through transcaval introducer sheaths. Transcaval access ports were closed with nitinol cardiac occluders. A core laboratory analyzed pre-discharge and 30-day abdominal computed tomograms. The Society of Thoracic Surgeons predicted risk of mortality was 9.6 ± 6.3%. RESULTS: Transcaval access was successful in 99 of 100 patients. Device success (access and closure with a nitinol cardiac occluder without death or emergency surgical rescue) occurred 98 of 99 patients; 1 subject had closure with a covered stent. Inpatient survival was 96%, and 30-day survival was 92%. Second Valve Academic Research Consortium (VARC-2) life-threatening bleeding and modified VARC-2 major vascular complications possibly related to transcaval access were 7% and 13%, respectively. Median length of stay was 4 days (range 2 to 6 days). There were no vascular complications after discharge. CONCLUSIONS: Transcaval access enabled TAVR in patients who were not good candidates for transthoracic access. Bleeding and vascular complications, using permeable nitinol cardiac occluders to close the access ports, were common but acceptable in this high-risk cohort. Transcaval access should be investigated in patients who are eligible for transthoracic access. Purpose-built closure devices are in development that may simplify the procedure and reduce bleeding. (Transcaval Access for Transcatheter Aortic Valve Replacement in People With No Good Options for Aortic Access; NCT02280824).

Left ventricular end-diastolic pressure affects measurement of fractional flow reserve.

BACKGROUND: Fractional flow reserve (FFR), the hyperemic ratio of distal (Pd) to proximal (Pa) coronary pressure, is used to identify the need for coronary revascularization. Changes in left ventricular end-diastolic pressure (LVEDP) might affect measurements of FFR. METHODS AND MATERIALS: LVEDP was recorded simultaneously with Pd and Pa during conventional FFR measurement as well as during additional infusion of nitroprusside. The relationship between LVEDP, Pa, and FFR was assessed using linear mixed models. RESULTS: Prospectively collected data for 528 cardiac cycles from 20 coronary arteries in 17 patients were analyzed. Baseline median Pa, Pd, FFR, and LVEDP were 73 mmHg, 49 mmHg, 0.69, and 18 mmHg, respectively. FFR<0.80 was present in 14 arteries (70%). With nitroprusside median Pa, Pd, FFR, and LVEDP were 61 mmHg, 42 mmHg, 0.68, and 12 mmHg, respectively. In a multivariable model for the entire population LVEDP was positively associated with FFR such that FFR increased by 0.008 for every 1-mmHg increase in LVEDP (beta=0.008; P<0.001), an association that was greater in obstructed arteries with FFR<0.80 (beta=0.01; P<0.001). Pa did not directly affect FFR in the multivariable model, but an interaction between LVEDP and Pa determined that LVEDP's effect on FFR is greater at lower Pa. CONCLUSIONS: LVEDP was positively associated with FFR. The association was greater in obstructive disease (FFR<0.80) and at lower Pa. These findings have implications for the use of FFR to guide revascularization in patients with heart failure. SUMMARY FOR ANNOTATED TABLE OF CONTENTS: The impact of left ventricular diastolic pressure on measurement of fractional flow reserve (FFR) is not well described. We present a hemodynamic study of the issue, concluding that increasing left ventricular diastolic pressure can increase measurements of FFR, particularly in patients with FFR<0.80 and lower blood pressure.

Comparison of lipid deposition at coronary bifurcations versus at nonbifurcation portions of coronary arteries as determined by near-infrared spectroscopy.

Atherosclerosis has been shown to develop preferentially at sites of coronary bifurcation, yet culprit lesions resulting in ST-elevation myocardial infarction do not occur more frequently at these sites. We hypothesized that these findings can be explained by similarities in intracoronary lipid and that lipid and lipid core plaque would be found with similar frequency in coronary bifurcation and nonbifurcation segments. One hundred seventy bifurcations were identified, 156 of which had comparative nonbifurcation segments proximal and/or distal to the bifurcation. We compared lipid deposition at bifurcation and nonbifurcation segments in coronary arteries using near-infrared spectroscopy (NIRS), a novel method for the in vivo detection of coronary lipid. Any NIRS signal for the presence of lipid was found with similar frequency in bifurcation and nonbifurcation segments (79% vs 74%, p = NS). Lipid core burden index, a measure of total lipid quantity indexed to segment length, was similar across bifurcation segments as well as their proximal and distal controls (lipid core burden index 66.3 ± 106, 67.1 ± 116, and 66.6 ± 104, p = NS). Lipid core plaque, identified as a high-intensity focal NIRS signal, was found in 21% of bifurcation segments, and 20% of distal nonbifurcation segments (p = NS). In conclusion, coronary bifurcations do not appear to have higher levels of intracoronary lipid or lipid core plaque than their comparative nonbifurcation regions.

Alcohol septal ablation for obstructive hypertrophic cardiomyopathy: outcomes in young, middle-aged, and elderly patients.

OBJECTIVES: We compared the efficacy and safety of alcohol septal ablation (ASA) for obstructive hypertrophic cardiomyopathy (HCM) in young, middle-aged, and elderly patients. BACKGROUND: Intersociety guidelines suggest based on limited evidence that young patients with medically refractory symptoms of obstructive HCM should undergo surgical myectomy while elderly patients may be more appropriate for ASA. METHODS: Data for 360 patients undergoing 389 ASAs were prospectively collected and retrospectively analyzed according to age. RESULTS: Young (<45 years), middle-aged (45-64 years), and elderly (≥65 years) patients comprised 28, 40, and 32% of the study population, respectively. Young patients had thicker left ventricular septal walls at baseline, and elderly patients had more comorbidity and dyspnea. Resting, mean left ventricular outflow tract gradients (LVOTGs) were similar across the age groups at baseline (62, 66, and 68 mm Hg, respectively; P = NS for all comparisons). LVOTGs and dyspnea were significantly and similarly improved in all age groups immediately after ASA and through 12 months of follow-up (P < 0.001 for before and after comparisons; P = NS for intergroup comparisons). Complication rates were similar for young and middle-aged patients but higher for elderly patients (9.1 and 6.3% vs. 20.8%, respectively; P ≤ 0.016 for elderly vs. others). Mortality rates for young and middle-aged patients were lower than for elderly patients, but the differences were not statistically significant. CONCLUSIONS: Patients undergoing ASA had significant and similar improvements in LVOTGs and symptoms regardless of age. Procedural complications were increased in elderly patients, who had numerically but not statistically significantly higher mortality rates.

Comparison of percutaneous coronary intervention safety before and during the establishment of a transradial program at a teaching hospital.

This study sought to examine the safety of percutaneous coronary intervention (PCI) before and during de novo establishment of a transradial (TR) program at a teaching hospital. TR access remains underused in the United States, where cardiology fellowship programs continue to produce cardiologists with little TR experience. Establishment of TR programs at teaching hospitals may affect PCI safety. Starting in July 2009 a TR program was established at a teaching hospital. PCI-related data for academic years 2008 to 2009 (Y1) and 2009 to 2010 (Y2) were prospectively collected and retrospectively analyzed. Of 1,366 PCIs performed over 2 years, 0.1% in Y1 and 28.7% in Y2 were performed by TR access. No major complications were identified in 194 consecutive patients undergoing TR PCI, and combined bleeding and vascular complication rates were lower in Y2 versus Y1 (0.7% vs 2.0%, p = 0.05). Patients treated in Y2 versus Y1 and by TR versus transfemoral approach required slightly more fluoroscopy but similar contrast volumes and had similar procedural durations, lengths of stay, and predischarge mortality rates. PCI success rates were 97% in Y1, 97% in Y2, and 98% in TR cases. TR PCIs were performed by 13 cardiology fellows and 9 attending physicians, none of whom routinely performed TR PCI previously. In conclusion, de novo establishment of a TR program improved PCI safety at a teaching hospital. TR programs are likely to improve PCI safety at other teaching hospitals and should be established in all cardiology fellowship training programs.

Meta-analyses of septal reduction therapies for obstructive hypertrophic cardiomyopathy: comparative rates of overall mortality and sudden cardiac death after treatment.

BACKGROUND: Septal reduction for obstructive hypertrophic cardiomyopathy may be performed by surgical myectomy or alcohol septal ablation (ASA). Unlike surgical myectomy, ASA creates an intramyocardial scar that may potentiate the risk of ventricular arrhythmias and sudden cardiac death (SCD). METHODS AND RESULTS: Systematic reviews for ASA and surgical myectomy were performed. Study selection and data extraction were completed independently by 2 investigators. Comparative data analyses were completed using a random effects model and regression analysis. Kappa statistics for agreement on initial study inclusion were high for both ASA (0.78; 95% CI, 0.68 to 0.88) and surgical myectomy studies (0.95; 95% CI, 0.84 to 1.0). Nineteen ASA studies (2207 patients) and 8 surgical myectomy studies (1887 patients) were included. Median follow-up was shorter for ASA than for myectomy studies (51 versus 1266 patient-years; P<0.001). For ASA and surgical myectomy, unadjusted rates (events/patient-years) of all-cause mortality (0.021 versus 0.018, respectively; P=0.37) and SCD (0.004 versus 0.003, respectively; P=0.36) were similar. Patients treated with ASA were older (weighted mean, 55 versus 44 years; P<0.001) and had less septal hypertrophy (weighted mean, 21 versus 23 mm; P<0.001) compared with those treated with myectomy. After adjustment for available baseline characteristics, odds ratios for treatment effect on all-cause mortality and SCD were 0.28 (95% CI, 0.16 to 0.46) and 0.32 (95% CI, 0.11 to 0.97), respectively, favoring ASA. CONCLUSIONS: Rates of all-cause mortality and SCD after both ASA and surgical myectomy were similarly low. Adjusted for baseline characteristics, the odds ratios for treatment effect on all-cause mortality and SCD were lower in ASA cohorts compared with surgical myectomy cohorts.

Altered fibroblast function following myocardial infarction.

Adequate wound healing and scar formation is an essential response to myocardial infarction (MI), and fibroblasts are primary cellular components regulating the process. How fibroblast functions are altered post-MI and to what extent these abnormalities persist in vitro is not well understood. Accordingly, we isolated myocardial fibroblasts from MI and non-MI (remote) regions at 7 days post-MI (n=35) and from the free wall and septum of unoperated control C57BL/6 mice (n=14). Proliferation was increased 182+/-28% in MI, but not in remote, fibroblasts compared with unoperated controls (P=0.01). Migration decreased 61+/-8%, adhesion to laminin decreased 79+/-8%, adhesion to collagen IV increased 196+/-27%, and collagen synthesis increased 169+/-24% in fibroblasts isolated from the MI region (all P<0.05). Migration, adhesion, and collagen synthesis changes were similar in remote fibroblasts, and the phenotypic differences were maintained through passage four. Transforming growth factor beta1 (TGFbeta1) is a bioactive molecule that has been shown to affect fibroblast function. Stimulation of unoperated control fibroblasts with 10 ng/ml TGFbeta(1) increased proliferation 137+/-7% (P=0.03 vs. unstimulated), increased adhesion to collagen IV 149+/-6% (P<0.01), and increased collagen I levels 187+/-10% (P=0.01). TGFbeta1 may, therefore, explain some of the changes in post-MI fibroblast phenotype. These data demonstrate for the first time region specific alterations in post-MI fibroblast biology that are maintained in vitro. Additionally, our model provides a novel in vitro template for examining the cellular mechanisms of wound healing and scar formation post-MI.