Simultaneous TAVR and TMVR-in-MAC guided by 3D modelling and prosthesis modification: a case report

Abstract

Background

Severe aortic stenosis (AS) with concomitant mitral annular calcification (MAC) presents substantial procedural and surgical challenges, and simultaneous transcatheter treatment remains rare. This case adds to the emerging literature by demonstrating a hybrid approach using transfemoral transcatheter aortic valve replacement (TAVR) and transapical transcatheter mitral valve replacement (TMVR)-in-MAC supported by patient-specific 3D-printed simulation and prosthesis modification.

Case summary

A 68-year-old woman with severe obesity, diabetes, chronic kidney disease, prior thoracic surgery, and a pacemaker presented with progressive dyspnoea. Echocardiography showed severe AS and functional mitral stenosis due to extensive MAC. Given prohibitive surgical risk, the Heart Team pursued a percutaneous strategy. A transfemoral self-expanding aortic transcatheter heart valve (THV) was partially deployed for annular anchoring, followed by transapical TMVR with a balloon-expandable valve modified with a polyethylene terephthalate skirt. Pre-procedural simulation with a patient-specific 3D-printed model guided implant depth and informed the decision for prosthesis modification. Both valves were implanted successfully with no paravalvular leak; a moderate left ventricular outflow tract (LVOT) gradient was noted.

Discussion

Simultaneous TAVR and TMVR in MAC is rare and technically challenging. This case shows that patient-specific 3D-printed modelling can support procedural planning and device modification, enabling a feasible hybrid transcatheter strategy with favourable clinical outcomes in a high-risk patient.

Learning points.

• Patient-specific 3D-printed heart models can enhance procedural planning, guide implant strategy, and inform prosthesis modification in complex valve interventions.

• Simultaneous transcatheter aortic and mitral valve replacement is a feasible treatment option in carefully selected patients with severe aortic stenosis and mitral annular calcification who are at prohibitive surgical risk.

Introduction

Severe aortic stenosis (AS) with concomitant mitral annular calcification (MAC) is a challenging clinical scenario due to technical complexity, increased surgical risk, and limited therapeutic options.^1,2 Surgical double-valve replacement in the setting of heavy MAC carries significant morbidity and mortality.² Growing experience with transcatheter mitral valve replacement (TMVR) and transcatheter aortic valve replacement (TAVR) offers alternative solutions for selected high-risk patients.^3,4 We present a case of severe AS with functional mitral stenosis due to MAC successfully treated with simultaneous transfemoral TAVR and transapical TMVR, guided by patient-specific 3D-printed heart modelling and prosthesis modification to optimize outcomes.²

Case presentation

A 68-year-old woman presented with progressive exertional dyspnoea (NYHA III) without chest pain or syncope. Past medical history included permanent pacemaker (third-degree AV block), insulin-dependent type 2 diabetes, stage 3b chronic kidney disease, prior right mastectomy with radiotherapy, and severe obesity [body mass index (BMI) 44.4 kg/m²]. Physical examination revealed a systolic murmur consistent with AS; other findings were unremarkable.

Diagnostic assessment

Transthoracic echocardiography demonstrated severe AS and functional mitral stenosis from circumferential MAC (see  Supplementary material online, Figure S1). Left ventricular (LV) ejection fraction was 60% with elevated pulmonary pressures (estimated PASP 52 mmHg).

Three-dimensional cardiac CT reconstruction using 3Mensio software (Pie Medical Imaging, Maastricht, the Netherlands) showed an aortic valve calcium score of 454 mm³ Agatston units (AU) and MAC calcium score of 6140 mm³  (Figure 1) AU with predicted neo-LVOT area of 205 mm². A patient-specific 3D-printed heart model (Figure 2) was printed using an SL-500 3D printer (SpaceLab, Kazakhstan) with thermoplastic polyurethane material, providing flexible mechanical properties and accurate anatomic replication. A dedicated pre-procedural simulation session was conducted with the heart team, including interventional cardiologists and cardiac surgeons. Using this anatomically accurate model under fluoroscopic (x-ray) guidance, the team rehearsed a ‘demo’ transcatheter aortic valve deployment in the setting of MAC, enabling optimization of device selection, refinement of implant strategy, and anticipation of potential complications (Figure 3). Following the simulation, a CT scan of the 3D-printed model with both transcatheter valves in place was performed to further assess valve position and interaction within the calcified anatomy (Figure 4).

Figure 1.

(A) Mitral valve internal area measurement. (B) Calcium quantification demonstrating extensive circumferential mitral annular calcification.

Figure 2.

3D-printed anatomical model. (A) Patient-specific 3D-printed heart model. (B) The aortic annulus (blue) and mitral annulus (red) manually marked on the model.

Figure 3.

Key steps of demo dual-valve implantation in 3D-printed model. (A) Partial deployment of aortic THV under fluoroscopy. (B) Positioning of mitral THV under fluoroscopy. (C) Final deployment of aortic THV under fluoroscopy. (D) Both implanted valves visualized within the 3D-printed heart model.

Figure 4.

CT of 3D-printed model after simulation.

Intervention

Given the patient’s severe obesity (BMI 44.4 kg/m²), insulin-dependent diabetes, stage 3b chronic kidney disease, prior thoracic surgery with radiotherapy for breast cancer, and permanent pacemaker implantation, the Heart Team determined that she was at extremely high surgical risk. Surgical correction of severe MAC is technically challenging and associated with high morbidity and mortality, even in lower-risk patients. In this context, conventional double-valve surgery was deemed unfavourable, and a combined percutaneous approach (TAVR and TMVR-in-MAC) was selected as the most viable and least invasive therapeutic option. The interdependence between severe aortic and mitral stenosis made it essential to treat both valves in the same session to ensure immediate stability and optimize cardiac output. A transseptal route for TMVR would have resulted in a highly non-coaxial trajectory relative to the calcified mitral annulus, increasing the risk of malalignment and paravalvular leak (PVL). Therefore, transapical access was chosen to ensure a direct and coaxial delivery path for precise THV positioning.

Transfemoral TAVR

Via right femoral arterial access, a 29 mm self-expanding Evolut R (Medtronic) valve was advanced to the aortic annulus. Under rapid ventricular pacing at 130 bpm, the valve was partially deployed. The frame was expanded sufficiently to anchor the valve while remaining attached to the delivery system and fully functional. This strategy provided stability and prevented displacement of the aortic transcatheter heart valve during the subsequent mitral procedure.

Mitral THV modification and TMVR

Following partial deployment of the aortic valve, the procedure continued with TMVR. The mitral prosthesis 27.5 mm Myval (Meril Life Sciences Pvt. Ltd., India) was prepared on the back table. A custom 0.4-mm-thick polyethylene terephthalate (PET) skirt was manually sutured to the atrial side of the valve frame to partially cover the open struts on the upper half of the device (Figure 5). Careful fixation stitches were placed around the frame bars from outside-in, avoiding damage to the prosthetic leaflets. This modification served two main purposes: (i) to reduce the risk of PVL in the event of non-coaxial deployment and (ii) to allow a higher implant position (∼35%–40% of the valve above the mitral annulus) in order to mitigate LV outflow tract obstruction.

Figure 5.

Mitral THV modification with polyethylene terephthalate skirt.

A small left anterolateral thoracotomy at the fifth intercostal space provided transapical access. Purse-string sutures were placed at the LV apex, and a stiff guidewire was advanced into the left atrium under imaging guidance. A 14-Fr Python sheath (Meril Life Sciences Pvt. Ltd., India) was then introduced. The modified THV was crimped onto the Navigator delivery system (Meril Life Sciences Pvt. Ltd., India) and advanced across the calcified mitral annulus, positioned with approximately 60% of the frame ventricular and 40% atrial. Under rapid ventricular pacing, the balloon was initially inflated to 50% for alignment, then fully expanded to achieve final deployment.

After TMVR, the aortic valve was fully deployed by releasing the remaining attachment. Final fluoroscopy and TEE confirmed stable expansion of the aortic valve with trivial PVL. Haemostasis was achieved by tightening the apical purse strings; the thoracotomy was closed in standard fashion, and the femoral access site was closed percutaneously.

Follow-up and outcomes

Post-procedural echocardiography confirmed that the mitral valve prosthesis was well-seated without PVL, with a moderate LVOT mean pressure gradient of 12 mmHg and AV mean gradient of 11 mmHg (see  Supplementary material online, Figure S2). The aortic valve was expanded with trivial PVL.

At 8-month follow-up, the patient’s NYHA functional class improved to I, and TTE demonstrated a mean LVOT gradient of 11 mmHg (see supplementary material online, Figure S3) with normally functioning prostheses.

A timeline summarizing the key clinical events, including diagnostic assessment and management, is presented in Table 1.

Table 1.

Clinical timeline

Timepoint	Findings	Intervention/Decision
Admission	Severe AS + MAC	Evaluation started
Imaging	High gradient, CT analysis	3D model created
Planning	High surgical risk	Hybrid approach selected
Procedure	Valve implantation	TAVR → TMVR
Post-op	Stable, no PVL	Monitoring
Follow-up	Improved symptoms	Routine follow-up

AS, aortic stenosis; MAC, mitral annular calcification; PVL, paravalvular leak; TAVR, transcatheter aortic valve replacement; TMVR, transcatheter mitral valve replacement.

Discussion

This case illustrates the feasibility of a simultaneous transcatheter approach for complex dual-valve disease, as concomitant TAVR and TMVR in MAC remains exceedingly rare, with only a few cases previously described.^1,3 Unlike earlier reports that used a transapical approach for both valves, we combined transfemoral TAVR with transapical TMVR, using partial deployment of the aortic prosthesis to enhance stability and reduce the risk of embolization during TMVR. Notably, despite a relatively low aortic valve calcium score, severe stenosis was confirmed by haemodynamic parameters, reflecting known limitations of calcium quantification, particularly in female patients where leaflet fibrosis and reduced compliance may predominate. A key innovation was the use of a patient-specific 3D-printed model to support pre-procedural planning; 3D simulation has been increasingly applied for device sizing, implant depth optimization, and complication prediction in structural intervention.^5,6 In our patient, the model informed anatomic assessment and guided the decision to modify the mitral valve with a PET skirt to address two major concerns in MAC: PVL and LVOT obstruction. Despite these measures, a moderate LVOT gradient persisted, consistent with known limitations of TMVR in MAC, which—while feasible—is associated with high early mortality but sustained symptomatic improvement among survivors.⁷ The modification of the prosthesis represents an off-label approach and should be interpreted with caution, as long-term safety and durability data remain limited.

This case also underscores the importance of heart-team evaluation and patient selection, as surgical MVR in severe MAC carries substantial risk,⁸ while systematic review suggests percutaneous TMVR offers a meaningful alternative for carefully selected high-risk patients.⁹ However, the relatively short follow-up period limits conclusions regarding long-term valve durability and clinical outcomes.

Conclusion

Simultaneous transfemoral TAVR and transapical TMVR-in-MAC was successfully performed in a high-risk patient using 3D-printed modelling for planning and a custom PET skirt for valve modification. This case demonstrates that hybrid transcatheter strategies with patient-specific simulation can expand treatment options in complex dual-valve disease.

Lead author biography

Graduate of the 2nd Moscow State Medical Institute, 1981. Worked as cardiac surgeon in Kyrgyzstan and Turkey for 10 years, respectively. Upon returning to Kazakhstan in 2003, he trained a dedicated team of specialists and developed a country-wide cardiac surgical service, including pediatric cardiac surgery. In 2010, he was appointed the first CEO of the National Research Cardiac Surgery Center, which he had projected himself from scratch. He implemented many high-tech treatment methods, including the implantation of LVADs, and heart and lung transplantations. He brought several international trials to Kazakhstan and authored dozens of articles and several international patents in cardiac surgery.

Supplementary material

Supplementary material is available at European Heart Journal – Case Reports online.

Author contributions

Yuriy Pya (Supervision [lead]), Yerkezhan Raissov (Conceptualization, Methodology [equal], Writing—original draft, Writing—review & editing [lead]), Alimbayev Serik (Methodology, Supervision [equal]), Timur Lesbekov (Methodology [equal]), and Abdurashid Mussayev (Conceptualization [equal], Writing—original draft, Writing—review & editing [supporting])

Consent: Written informed consent was obtained from the patient for publication of this case and accompanying images in accordance with COPE and EHJ-Case Reports policies.

Funding

No external funding was received for this work.

Data availability

The data underlying this article are available within the article and in its Supplementary material.