Influence of continuously evolving transcatheter aortic valve implantation technology on cerebral oxygenation.

This study assessed the influence of the evolution in Transcatheter Aortic Valve Implantation technology on cerebral oxygenation. Cerebral oxygenation was measured continuously with Near-Infrared Spectroscopy and compared retrospectively between balloon-expandable, self-expandable and differential deployment valves which were implanted in 12 (34%), 17 (49%) and 6 patients (17%), respectively. Left and right SctO2 values were averaged at four time points and used for analysis (i.e. at baseline, balloon-aortic valvuloplasty, valve deployment, and at the end of the procedure). During balloon-aortic valvuloplasty and valve deployment, cerebral oxygenation decreased in patients treated with balloon or self-expandable valves (balloon-expandable: p = 0.003 and p = 0.002; self-expandable: p < 0.001 and p = 0.003, respectively). The incidence of cerebral desaturations below 80% of baseline was significantly larger in patients treated with balloon-expandable valves (p = 0.001). In contrast, patients who received differential deployment valves never experienced a cerebral desaturation below 80% of baseline. Furthermore, both the incidence and duration below a cerebral oxygenation of 55% was significantly different between balloon and self-expandable valves (p = 0.038 and p = 0.018, respectively). This study demonstrated that Transcatheter Aortic Valve Implantation procedures are associated with significant cerebral desaturations, especially during balloon-aortic valvuloplasty and valve deployment. Moreover, our results showed that latest innovations in Transcatheter Aortic Valve Implantation technology beneficially influenced the adequacy of cerebral perfusion.

Catheter Port Reversal in Citrate Continuous Veno-Venous Hemofiltration.

INTRODUCTION: Knowledge of effects of catheter port reversal (CathPR), when blood is withdrawn from the venous port and returned via the arterial port, often used in dysfunctional catheters in renal replacement therapy, is limited in the setting of citrate continuous veno-venous hemofiltration (CVVH). METHODS: In this open trial, post-filter ionized calcium (PfiCa), post-filter citrate concentration (PfCC), catheter recirculation, and solute clearance were measured before, during, and after 6 hours of CathPR, in well-functioning catheters. All other settings, including citrate settings, were left constant during the study. RESULTS: Twenty-three patients were included. Mean PfiCa before CathPR of 0.36 mmol/L (SD 0.06) decreased to 0.31 (0.04) after 2 hours (P = 0.002), 0.31 (0.04) (P = 0.002) at 4 hours, and 0.31 (0.04) at 6 hours (P = 0.001). Return to normal increased mean PfiCa to 0.34 (0.06) (P = 0.006). Mean PfCC rose from 592 mg/L (SD 164) before CathPR to 649 mg/L (190) after 2 hours (P = 0.045), to 696 mg/L (192) after 4 hours (P < 0.001), and to 657 mg/L (214) after 6 hours (P = 0.018). Return to normal decreased mean PfCC to 598 mg/L (184) (P = 0.024). Mean recirculation increased during CathPR (from 4.3% [0-8.7] before to 13.8% [9.7-22.2], P < 0.001). Urea, potassium, and creatinine clearances dropped significantly, but calcium clearance was unaffected. CONCLUSION: CathPR caused a significant decrease in PfiCA and increase in PfCC. Calcium handling differs from other solutes because of increases caused in citrate concentration and subsequent effects on calcium chelation. In citrate CVVH, CathPR in dysfunctional catheters should be limited in time, with intensive follow-up. Trial registration: ClinicalTrials.gov: NCT024600416. Registered 9 November 2015.

Myectomy and mitral repair through the left atrium in hypertrophic obstructive cardiomyopathy: the preferred approach for contemporary surgical candidates?

OBJECTIVE: Patients with hypertrophic obstructive cardiomyopathy due to diffuse hypertrophy extending to or below the papillary muscles are poor candidates for alcohol septal ablation and suboptimal candidates for transaortic septal myectomy. In addition, the outflow obstruction is often aggravated by an abnormal mitral valve and subvalvular apparatus. METHODS: We performed transatrial myectomy in 12 patients with diffuse hypertrophy, who were highly symptomatic despite maximal medical therapy. All had at least moderate mitral regurgitation and systolic anterior motion. The anterior mitral leaflet (AML) was detached from commissure to commissure, allowing an easy myectomy through this AML toward the base of the anterior papillary muscle, with mobility fully restored. The abnormal chordae from the septum to the anterior papillary muscle and AML were divided. The continuity of this AML was restored with augmentation using an autologous pericardial patch. The height of the posterior mitral leaflet was reduced and the repair completed using an oversized annuloplasty ring. RESULTS: The peak intraventricular gradients decreased spectacularly from 98.8 ± 6.29 to 19.2 ± 13.4 mm Hg (P < .001), and the systolic anterior motion and mitral regurgitation disappeared. One patient died of left ventricular diastolic dysfunction. All other patients left the hospital in New York Heart Association class I or II. CONCLUSIONS: We believe that this technique is preferable for patients with hypertrophic obstructive cardiomyopathy and diffuse hypertrophy extending to the midportion of the left ventricle or beyond. It results in disappearance of outflow tract gradients and allows correction of the mitral valve abnormality.