Transfemoral transcatheter aortic valve replacement for severe aortic stenosis with concomitant left ventricular diverticulum: a case report.

Background: Left ventricular diverticulum (LVD) is a rare cardiac malformation in patients with severe aortic stenosis (AS). Transcatheter aortic valve replacement (TAVR) is not recommended due to the risk of diverticulum injury. However, for patients considered inoperable or at high surgical risk, TAVR might be the only treatment option. The safety and feasibility of TAVR for severe AS with concomitant LVD are still unclear. Case summary: An 80-year-old Asian woman complaining of shortness of breath was admitted to our hospital, whose echocardiogram showed calcified severe AS and a diverticulum in the left ventricular apex. A transfemoral 26 mm Venus-A prosthetic aortic valve was successfully implanted. Pre- and post-procedural cardiac magnetic resonance imaging revealed a remarkable volume reduction of LVD. Discussion: Transfemoral TAVR was not preferred because the straight-tip hydrophilic wire and catheter tip could injure the fragile diverticulum wall. If we could avoid the injury of the diverticulum, TAVR would be a good option for patients at high surgical risk.

Transfemoral transcatheter aortic valve replacement (TAVR) could be performed safely for severe aortic stenosis with concomitant left ventricular diverticulum (LVD) in selected patients.

Careful manipulation of wires and catheters is important to avoid the injury of LVD.

The volume of the LVD diminished remarkably after TAVR.

Introduction

Left ventricular diverticulum (LVD) is a rare cardiac malformation in patients with severe aortic stenosis (AS). In this setting, surgical aortic valve replacement (SAVR) is recommended as superior to transcatheter aortic valve replacement (TAVR) according to the guidelines.[1,2] However, for patients considered inoperable or at high surgical risk, TAVR might be the only treatment option. Here, we present a case of transfemoral TAVR with a self-expanding valve in severe AS with concomitant LVD.

Case

An 80-year-old Asian woman was admitted to our institute complaining of increasing shortness of breath with New York Heart Association Class III heart failure symptoms. She had a history of smoking, hypertension, heart failure, and persistent atrial fibrillation. On physical examination, she had a systolic ejection murmur and an irregular rhythm. Blood tests showed no abnormalities except for plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) level was 12 143.00 pg/mL (reference level, <125 pg/mL).

(A) Pre-procedural cardiac magnetic resonance imaging showing the left ventricular diverticulum (arrow) at the end of the systolic phase. (B) Pre-procedural cardiac magnetic resonance imaging showing the left ventricular diverticulum (arrow) at the end of the diastolic phase. (C) Post-procedural cardiac magnetic resonance imaging showing the left ventricular diverticulum (arrow) at the end of the systolic phase. (D) Post-procedural cardiac magnetic resonance imaging showing the left ventricular diverticulum (arrow) at the end of the diastolic phase.

Transthoracic echocardiogram showed severe calcified AS (peak velocity: 4.5–4.8 m/s, peak gradient: 81–90 mmHg, mean gradient: 50–56 mm Hg, aortic valve orifice area: 0.5 cm2, left ventricular ejection fraction: 41%) and a 10 × 12 mm diverticulum in the left ventricular apex.

Cardiac magnetic resonance imaging with gadolinium demonstrated severe AS with decreased systolic function of left and right ventricles, and a diverticulum in the left ventricular apex with ESV of 0.81 mL () and EDV of 0.35 mL (, Supplementary material online, ).

Preoperative CT showed severely calcified AS, with an annular perimeter of 79.4 mm, calcium above HU 850 of 583 mm3, and adequate coronary heights of 19 mm on the right and 11.5 mm on the left. The iliofemoral arteries are suitable for transfemoral access.

A MDT discussion was held to determine the treatment option for the patient. Due to a high STS score for risk of mortality of 8.3%, the patient was declined for SAVR. Considering the small neck of the LVD (13.8 × 8.2 mm, and ), if the stiff wire could be shaped into a big enough curve, the possibility of injuring the LVD by the stiff wire would be greatly diminished. Transcatheter aortic valve replacement would be a reasonable option.

The maximal (A) and minimal (B) diameter of the neck of the left ventricular diverticulum. (C) The maximal and minimal diameter of the apical curve of the stiff wire.

Transcatheter aortic valve replacement was performed under general anaesthesia and transfemoral approach. A straight-tip soft hydrophilic wire (Terumo Medical, Japan) supported by an AL1 catheter was carefully controlled to cross the aortic valve. To avoid injuring the LVD, the wire and catheter were controlled carefully not to exceed more than half of the left ventricle (see Supplementary material online, ), then exchanged for a pre-shaped Lunderquist stiff wire (Cook Medical Inc., loop diameter: 29.5 × 23.5 mm, ). After pre-dilatation with a 23-mm balloon (NuMED Inc., Hopkinton, NY, USA), a 26 mm Venus-A prosthetic valve (Venus MedTech Inc., HangZhou) was deployed successfully. Final aortography (see Supplementary material online, ) and transoesophageal echocardiography showed a well-functioned valve with trivial paravalvular leakage. Cardiac magnetic resonance imaging 1 month after the procedure showed a diminished volume of the diverticulum (0.31 mL at ESV () and 0.17 mL at EDV (, Supplementary material online, ). Blood tests also showed that NT-proBNP level had been decreased to 3532.00 pg/mL.

Discussion

Left ventricular diverticulum is a rare cardiac malformation characterized by a localized outpouching from the cardiac chamber. For AS patients with concomitant apical diverticulum, the standard therapy is SAVR and LVD removal. Transapical TAVR and following excluding of the ventricle diverticulum during the same procedure, as reported by Ferrari et al.[3] in 2013, is an acceptable option for patients at high surgical risk. However, the transapical approach has a risk of bleeding, myocardial injury, and the invasiveness of ventriculostomy and thoracotomy. Sometimes, patients cannot tolerate the invasiveness of this approach. Transfemoral TAVR was not preferred because the straight-tip hydrophilic wire and catheter tip could injure the fragile diverticulum wall. If we could avoid the injury of the diverticulum, TAVR would be a good option for patients at high surgical risk.

For this case, the diverticulum was located at the left ventricle apex, and we could control the wire and catheter not to exceed more than half of the left ventricle, thus not touching the diverticulum. The neck of the diverticulum was very small, not allowing the pre-shaped stiff wire to enter. So the procedure could be finished safely without any complications. During the procedure, the most important thing is the careful manipulation of the straight-tip wire and AL catheter. After exchanging to the pre-shaped wire, it is as safe as the routine TAVR procedure.

Theoretically, as left ventricular pressure declined after TAVR, the volume of the diverticulum could also decrease. In this case, we demonstrated that the volume of the diverticulum diminished remarkably after the procedure by pre- and post-procedure CMR.

Conclusion

This case suggests that transfemoral TAVR is safe and feasible for selected patients with severe AS and concomitant LVD.

Lead author biography

Dr Liang Guo, MD, PhD served as Associate Professor at Department of Cardiology, the First Hospital of China Medical University, Shenyang, China. He performed more 500 cases of coronary interventions and 30 cases of TAVR every year.

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Date	Event
Day 1	The patient was admitted to our institute complaining of increasing shortness of breath
Day 2	Pre-procedural transthoracic echocardiography (TTE) was performed, showing severe calcified severe AS and a 10 × 12 mm diverticulum in the left ventricular apex
Day 3	Pre-procedure computed tomography (CT) scan was performed
Day 4	Pre-procedural cardiac magnetic resonance imaging (CMR) was performed, showing a diverticulum in the left ventricular apex with end-systolic volume (ESV) of 0.81 mL (Figure 1A) and end-diastolic volume (EDV) of 0.35 mL (Figure 1B, Supplementary material online, Video S1)
Day 6	A multidisciplinary team (MDT) discussion was held. Due to a high Society of Thoracic Surgeons score (STS) for risk of mortality of 8.3%, the patient was declined for SAVR. Considering the small neck of the LVD (13.8 × 8.2 mm), if the stiff wire could be shaped into a big enough curve, the possibility of injuring the LVD by the stiff wire would be greatly diminished. Transcatheter aortic valve replacement would be a reasonable option
Day 8	Transfemoral TAVR was performed. Aortography and transoesophageal echocardiography showed a well-functioned aortic valve with trivial paravalvular leakage
Day 10	Patient discharge
Month 1	Cardiac magnetic resonance imaging showed diminished volume of the diverticulum (0.31 mL at ESV (Figure 1C) and 0.17 mL at EDV (Figure 1D, Supplementary material online, Video S4).