Feasibility and safety of parallel Shockwave balloon percutaneous mitral commissurotomy for degenerative mitral stenosis

Treatment of degenerative mitral valve stenosis (DMVS) is challenging, with most percutaneous/surgical techniques carrying high morbidity and mortality. Conventional percutaneous mitral commissurotomy (PMC) is often contraindicated, as most cases present with heavily calcified leaflets and/or absence of commissural fusion. In this setting, the use of lithotripsy (LT) has emerged as a novel approach in these patients (pts), with favorable hemodynamic, clinical and safety outcomes.

To describe a novel technique of PMC with 2 parallel shockwave LT balloons through a single transseptal puncture and characterize its hemodynamic and safety results.

Retrospective, single center analysis of pts with DMVS, who were deemed unsuitable for surgery and were scheduled to undergo PMC with shockwave LT, after multidisciplinary HeartTeam evaluation.

Three pts were submitted to PMC with shockwave LT (median age 73 years, 67% female). Two pts were deemed unsuitable for surgery due to porcelain aorta, whereas one pt was rejected due to advanced age and comorbidities. All pts presented significant leaflet and mitral annular calcification (MAC) and were not eligible for percutaneous valve-in-MAC.

The procedure was performed as described:

1. Echocardiography for evaluation of transmitral gradients (TMG), estimated MV area and mitral regurgitation;

2. Establishment of 2 arterial and 2 venous accesses. Deployment of a cerebral embolic protection device (Sentinel®) and a pigtail catheter through the arterial accesses. Progression of an intracardiac echocardiography probe (AcuNav®) and an over-the-wire (OTW) SL1® sheath to the right atrium;

3. Transseptal puncture with a BRK® needle. OTW progression of 2 steerable sheaths (Agilis®) and pigtail catheters to the left atrium. Invasive assessment of left ventricular pressure and TMG;

4. Progression of a V18® guidewire through the pigtail catheter and subsequent delivery of two 12mm Shockwave® E6 balloons;

5. Sequential and simultaneous balloon inflations with LT delivery (30 pulses per cycle; total 540–600 pulses) without ventricular pacing. Assessment of final TMG.

6. Retrieval of cerebral embolic protection device and access closure.

Median noninvasive and invasive preprocedural TMG were 16mmHg and 11mmHg, respectively. After PMC, significant improvements were observed, with final noninvasive and invasive TMG of 7mmHg. No worsening of baseline regurgitation was observed. There were no immediate major complications.

This case series illustrates the feasibility and safety of MV balloon valvuloplasty using Shockwave intravascular LT in inoperable pts with DMVS. The approach achieved significant hemodynamic improvement without increasing regurgitation or causing procedural complications. These findings support LT-assisted MV valvuloplasty as a potential option for pts with unfavorable anatomy, unsuitable for conventional percutaneous or surgical therapy.For image description, please refer to the figure legend and surrounding text.  For image description, please refer to the figure legend and surrounding text.