Avoidance strategy for coronary obstruction in patient with anomalous origin of the left circumflex undergoing transcatheter aortic valve implantation

Excerpt

A 76-year-old woman with a history of stroke with severe hemiplegia was hospitalized for decompensated heart failure due to severe aortic stenosis (The Society of Thoracic Surgeons scores of predicted risk of mortality 4.05 points). The local heart-team decided to perform a transcatheter aortic valve implantation (TAVI) instead of surgical aortic valve replacement (SVAR) in view of her poor mobility (Clinical Frailty Scale; 7) caused by hemiplegia which might not be able to rehabilitate enough after the procedure. Pre-procedural computed tomography (CT) scans revealed an anomalous origin of the left circumflex coronary artery (LCX) from the right coronary cusp below the ostium of the right coronary artery, running through between the aortic valve apparatus and right atrium (Fig. 1A, B). Coronary heights at the RCA, LAD, and LCX were 12.60, 14.20, and 12.60 mm, respectively. In the local heart-team discussion, we had concerned that coronary obstruction at the mid-portion of LCX between aortic valve complex and pulmonary artery might be caused by mechanical compression of pre-dilatation or THV implantation. However, we had not expected for coronary occlusion at the ostium of coronary arteries because coronary heights were enough high to implant THV safely. Therefore, we determine to perform coronary protection if pre-dilatation led to coronary obstruction. During TAVI, the LCX was transiently occluded (Fig. 1C, D) after full inflation of a 20-mm balloon (Tokai Medical, Aichi, Japan) for pre-dilatation. A 0.014-inch guidewire and a 2.5 × 15 mm semi-compliant balloon (SAPPHIRE3; OrbusNeich, Wanchai, Hong Kong) were delivered to the LCX for coronary protection. Pre-procedural CT scans (area 341.1 mm², perimeter 68.0 mm) recommended a 23-mm SAPIEN3 valve (Edwards Lifesciences, Irvine, California); however, a 20-mm SAPIEN3 valve was selected based on previous literature that showed coronary obstruction using the recommended 23-mm transcatheter heart valve (THV) [1]. The LCX had 75% stenosis during full inflation of the balloon for THV expansion (Fig. 1E, F). Mild paravalvular leakage was detected; therefore, post-dilatation was performed by inflating the THV balloon with 1 mL more. Since there was no change in coronary stenosis despite deflating the balloon for BAV, intracoronary nitrate was administrated due to the suspicion of a vasospasm caused by mechanical compression of the THV. Subsequently, the LCX expanded without remaining stenosis (Fig. 1G). An intravascular ultrasound revealed no organic lesion (Fig. 1H–L); therefore, a vasospasm may have caused the LCX stenosis. In a TAVI procedure, the coronary artery with anomalous origin is at high-risk for coronary obstruction; however, the combination of a one-size-smaller THV and the intracoronary administration of nitrate may reduce this risk and avoid inappropriate coronary stenting.

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