Srdjan Jelacic

BACKGROUND: Mitral annular calcification with valve dysfunction remains a challenging syndrome. Operative risk is high, and available transcatheter therapies are limited. METHODS: This study describes our initial experience with a novel procedure to address large mitral annuli when no surgical or trial-based transcatheter mitral valve replacement device is available. The rationale was to shorten the intercommissural distance using commissural mitral transcatheter edge-to-edge repair (TEER) followed by valve-in-mitral annular calcification transcatheter mitral valve replacement with a balloon-expandable aortic valve platform. Patients with long intercommissural distances and large mitral annulus areas were selected based on a high perceived risk of transcatheter valve embolization. Patients underwent mitral TEER with MitraClip in a commissural position, followed immediately by transseptal transcatheter mitral valve replacement with a 29 mm SAPIEN 3 valve. RESULTS: Thirteen patients were included. Median intercommissural distance and annular area were 39.1 mm and 930 mm ² , respectively. Commissural mitral TEER was successful in all patients with no instances of single leaflet detachment. In 10 of 13 instances, an NTW device size was used. In 12 of 13 patients, valve implantation was successful, including 1 case that required a second valve for atrial positioning of the first valve. In 1 case, frank valve embolization into the left atrium occurred. Among the 12 successful cases, paravalvular leak was 1+ or less, and there were no instances of paravalvular leak adjacent to the TEER device. CONCLUSIONS: In patients with large annuli and sufficient annular calcium, a hybrid mitral TEER and valve replacement with the SAPIEN platform can be successfully used to facilitate transcatheter mitral valve replacement.

Background: The accuracy and precision of currently available, widely used acceleromyograph and electromyograph neuromuscular blockade monitors have not been well studied. In addition, the normalization of the train-of-four ratio from acceleromyography (train-of-four ratio [T4/T1] divided by the baseline train-of-four ratio) has not been validated in comparison to mechanomyography. Methods: Enrolled patients had surgery under general anesthesia with a supraglottic airway and without any neuromuscular blocking drugs. Three acceleromyograph monitors, three electromyograph monitors, and a mechanomyograph built in the authors’ laboratory were tested. Most patients had an electromyograph and the mechanomyograph on one arm and a third monitor on the contralateral arm. Train-of-four ratios were collected every 12 to 20 s for the duration of the anesthetic. At least 1,000 train-of-four ratios were recorded for each device. Gauge repeatability and reproducibility analysis was performed. Results: Twenty-eight patients were enrolled. In total, 9,498 train-of-four ratio measurements were collected. Since no neuromuscular blocking drugs were used, the expected train-of-four ratio was 1.0. All of the acceleromyograph monitors produced overshoot in the train-of-four ratio (estimated means, 1.10 to 1.13) and substantial variability (gauge SDs, 0.07 to 0.18). Normalization of the train-of-four ratio measured by acceleromyography improved the estimated mean for each device (0.97 to 1.0), but the variability was not improved (gauge SDs, 0.06 to 0.17). The electromyograph and the mechanomyograph monitors produced minimal overshoot (estimated means, 0.99 to 1.01) and substantially less variation (gauge SDs, 0.01 to 0.02). For electromyography and mechanomyography, 0.3% of all train-of-four ratios were outside of the range 0.9 to 1.1. For acceleromyography, 27 to 51% of normalized train-of-four ratios were outside the range of 0.9 to 1.1. Conclusions: Three currently available acceleromyograph monitors produced overshoot and substantial variability that could be clinically significant. Normalization corrected the overshoot in the average results but did not reduce the wide variability. Three electromyograph monitors measured the train-of-four ratio with minimal overshoot and variability, similar to a mechanomyograph. Editor’s Perspective: What We Already Know about This Topic: What This Article Tells Us That Is New: