Faculty Bibliography

Acute kidney injury (AKI) is associated with a poor prognosis after transcatheter aortic valve replacement (TAVR). A paucity of data exists regarding the incidence and effect of AKI after TAVR using the new recommended Valve Academic Research Consortium criteria. At Columbia University Medical Center, 218 TAVR procedures (64.2% transfemoral, 35.8% transapical) were performed from 2008 to July 2011. The creatinine level was evaluated daily until discharge. Using the Valve Academic Research Consortium definitions, the 30-day and 1-year outcomes were compared between patients with significant AKI (AKI stage 2 or 3) and those without significant AKI (AKI stage 0 or 1). Significant AKI occurred in 18 patients (8.3%). Of these 18 patients, 10 (55.6%) had AKI stage 3 and 9 (50%) required dialysis. AKI was associated with a lower baseline mean transvalvular gradient (37.6 +/- 11.4 vs 45.6 +/- 14.8 mm Hg for no AKI, p = 0.03). After TAVR, the AKI group had a greater hemoglobin decrease (3.6 +/- 2.0 vs 2.4 +/- 1.3 g/dl, p = 0.01), greater white blood cell elevation at 72 hours (21.09 +/- 12.99 vs 13.18 +/- 4.82 x 10(3)/mul, p = 0.001), a more severe platelet decrease (118 +/- 40 vs 75 +/- 43 x 10(3)/mul, p <0.0001), and longer hospitalization (10.7 +/- 6.4 vs 7.7 +/- 8.5 days, p <0.001). One stroke (5.6%) occurred in the AKI group compared with 3 (1.5%) in the group without AKI (p = 0.29). The 30-day and 1-year rates of death were significantly greater in the AKI group than in the no-AKI group (44.4% vs 3.0%, hazard ratio 18.1, 95% confidence interval 6.25 to 52.20, p <0.0001; and 55.6% vs 16.0%, hazard ratio 6.32, 95% confidence interval 3.06 to 13.10, p <0.0001, respectively). Periprocedural life-threatening bleeding was the strongest predictor of AKI after TAVR. In conclusion, the occurrence of AKI, as defined by the Valve Academic Research Consortium criteria, is associated with periprocedural complications and a poor prognosis after TAVR.

AIMS: To describe patient radiation utilisation during transcatheter aortic valve replacement (TAVR) on a series of consecutive patients. METHODS AND RESULTS: Data on radiation exposure were prospectively collected for consecutive patients undergoing TAVR and percutaneous coronary interventions at our centre. Radiation dose during the procedure was recorded using the US Food and Drug Administration (FDA) reference point (Ka,r) and the dose area product (PKA). In addition to quantifying overall radiation doses during TAVR, radiation exposure during transfemoral (TF) (n=79) and transapical (TA) (n=26) cases was compared. The median radiation dose during TAVR was 1,639 mGy (983-2,420), or 188 (106-321) Gy*cm2. Radiation dose was significantly lower among TA patients using either the reference point (TA: 946 [777-1,261] vs. TF: 1,932 [1,383-2,614] mGy; p<0.001) or the dose area product (TA: 89 [60-115] vs. TF: 236 [164-338] Gy*cm2; p<0.001). Fluoroscopy time was lower for TA patients (TA: 10 [8-11] vs. TF: 30 [24-34] minutes; p<0.001). Operators experience did not affect radiation exposure for TF cases. CONCLUSIONS: Radiation exposure during TAVR appears similar to other percutaneous coronary interventions of moderate complexity. Radiation doses were significantly lower for TA procedures. A higher dose of radiation in TF patients may be related to additional imaging requirements to optimise percutaneous vascular access and closure.

Transcatheter aortic valve implantation (TAVI) has been increasingly recognized as a curative treatment for severe aortic stenosis (AS). Despite important improvements in current device technology and implantation techniques, specific complications still remain and warrant consideration. Vascular complications and peri-procedural neurological events were the first concerns to emerge with this new technology. Recently, significant post procedural para-valvular leak has been shown to be more frequent after TAVI than after surgical aortic valve replacement (SAVR), and its potential association with worse long-term prognostic has raised concerns. In moving toward treatment of lower risk populations, structural integrity and long-term durability of heat valve prosthesis are becoming of central importance. Emerging technologies and newer generations of devices seem promising in dealing with these matters.

Surgical aortic valve replacement (SAVR) is currently the standard of care to treat patients with severe symptomatic aortic stenosis (AS) and is generally accepted to alleviate symptoms and prolong survival. Based on the results of randomized trials, transcatheter aortic valve implantation (TAVI) is the new standard of care for patients with symptomatic AS who are deemed 'inoperable'. Debatably, TAVI is also an alternative to SAVR in selected patients who are at high risk but operable. As we approach 10 years of clinical experience with TAVI, with over 50 000 implantations in 40 countries, a review of the current literature and clinical outcomes with this rapidly evolving technology is appropriate.

OBJECTIVES: This study sought to identify incidence, predictors, and impact of vascular complications (VC) after transfemoral (TF) transcatheter aortic valve replacement (TAVR). BACKGROUND: VC after TF-TAVR are frequent and may be associated with unfavorable prognosis. METHODS: From the randomized controlled PARTNER (Placement of AoRTic TraNscathetER Valve) trial, a total of 419 patients (177 from cohort B [inoperable] and 242 from cohort A [operable high-risk]) were randomly assigned to TF-TAVR and actually received the designated treatment. First-generation Edwards-Sapien valves and delivery systems were used, via a 22- or 24-F sheath. The 30-day rates of major and minor VC (modified Valve Academic Research Consortium definitions), predictors, and effect on 1-year mortality were assessed. RESULTS: Sixty-four patients (15.3%) had major VC and 50 patients (11.9%) had minor VC within 30 days of the procedure. Among patients with major VC, vascular dissection (62.8%), perforation (31.3%), and access-site hematoma (22.9%) were the most frequent modes of presentation. Major VC, but not minor VC, were associated with significantly higher 30-day rates of major bleeding, transfusions, and renal failure requiring dialysis, and with a significantly higher rate of 30-day and 1-year mortality. The only identifiable independent predictor of major VC was female gender (hazard ratio [HR]: 2.31 [95% confidence interval (CI): 1.08 to 4.98], p = 0.03). Major VC (HR: 2.31 [95% CI: 1.20 to 4.43], p = 0.012), and renal disease at baseline (HR: 2.26 [95% CI: 1.34 to 3.81], p = 0.002) were identified as independent predictors of 1-year mortality. CONCLUSIONS: Major VC were frequent after TF-TAVR in the PARTNER trial using first-generation devices and were associated with high mortality. However, the incidence and impact of major VC on 1-year mortality decreased with lower-risk populations.