Balloon Aortic Valvuloplasty as a Bridge Therapy in Acute Valve Syndrome: A Narrative Review of Evidence Gaps and Future Directions

Abstract

Acute valve syndrome represents a high-acuity, decompensated presentation of severe aortic stenosis (AS), often manifesting as acute heart failure, cardiogenic shock, or cardiac arrest. Transcatheter aortic valve replacement (TAVR) remains the only durable therapy for severe AS in patients with prohibitive surgical risk, yet acute valve syndrome patients may be too unstable for standard preprocedural planning. Balloon aortic valvuloplasty (BAV) has re-emerged as a bridge strategy that can provide rapid hemodynamic stabilization and permit subsequent valve replacement. Registry analyses report lower mortality in emergent TAVR compared with BAV, but these comparisons are confounded by procedural indication and unmatched AS severity. Smaller hemodynamically characterized cohorts suggest that selected patients who stabilize after BAV and proceed to TAVR may achieve outcomes comparable to direct TAVR, although these studies remain underpowered for definitive inference. In this narrative review, we evaluate evidence comparing BAV-bridged strategies with emergent TAVR, identify key evidence gaps, and discuss how acute hemodynamic status may inform Heart Team decision-making.

Graphical Abstract

Graphical Abstract: Integrated severity assessment framework for acute valve syndrome. Conceptual model showing how AVS phenotype, cardiac damage stage (stage 0–4), and Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock stage (A–E) may inform treatment selection. Recommended strategies are mapped across severity: expedited TAVR (green) for stable patients; emergent TAVR ± MCS (yellow) for moderate instability; BAV-bridge ± MCS (orange) for hemodynamically unstable AVS patients requiring stabilization before definitive interventionAbbreviations: AVS, acute valve syndrome; BAV, balloon aortic valvuloplasty; CTA, computed tomography angiography; MCS, mechanical circulatory support; TAVR, transcatheter aortic valve replacement.

Highlights

• •Acute valve syndrome carries more than twofold mortality risk compared with elective aortic stenosis presentation.
• •Direct urgent transcatheter aortic valve replacement may be favorable when planning and implantation are feasible.
• •Balloon aortic valvuloplasty benefit attenuates without definitive transcatheter aortic valve replacement.

Introduction

Balloon aortic valvuloplasty (BAV) was initially proposed as definitive therapy for severe calcific aortic stenosis (AS) in patients deemed unsuitable for surgery.¹ Early experience demonstrated significant reductions in transvalvular gradients and symptomatic improvement.² However, subsequent studies revealed limited durability, high restenosis rates, and a lack of long-term survival benefit, largely confining BAV to palliative use.3, 4, 5 Analysis from the PARTNER trial revealed that inoperable AS patients receiving BAV showed improved survival at 3 months, with outcomes converging at 6 months compared to medical management.⁶

The advent of transcatheter aortic valve replacement (AVR) (TAVR) transformed the management of severe AS, offering durable hemodynamic relief and improved survival across inoperable, high-risk,^7,8 intermediate-risk,⁹ and low-risk populations.¹⁰ Although TAVR initially prompted increased BAV utilization, with procedural volumes rising more than fivefold from 2004 to 2013, BAV rates have subsequently declined at mature TAVR centers.^11,12 Contemporary indications include bridging of hemodynamically unstable patients to definitive intervention, assessment of therapeutic response, facilitation of urgent noncardiac surgery, and palliation in non-AVR candidates.^12,13

In current practice, BAV primarily serves as a bridge therapy for patients too unstable for emergent TAVR and its requisite preprocedural planning or who require transfer to TAVR-capable centers.¹³ Standardized TAVR planning typically includes echocardiography, contrast-enhanced computed tomography (CT), and cardiac catheterization. In patients with cardiogenic shock, respiratory failure, and renal failure, these studies may be temporarily infeasible. BAV at the time of coronary angiography may relieve critical gradients to permit hemodynamic and end-organ recovery, facilitating definitive AVR during the same or subsequent admission.¹⁴

Both the 2020 American College of Cardiology/American Heart Association guidelines (class IIB) and 2025 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines allow BAV as a temporizing measure in hemodynamically unstable patients^15,16 but provide limited granularity regarding patient selection. Furthermore, these recommendations rest largely on observational data.^17,18

This review explores a clinically important question: among acute valve syndrome (AVS) patients requiring urgent valve intervention, when is direct urgent/emergent TAVR feasible, and when is BAV best used as a temporizing measure?

Pathophysiology of Acute Decompensation

Contemporary data suggest that symptomatic, severe AS patients who remain untreated face mortality risk of up to 50% at 1 year.¹⁹ Chronic AS induces compensatory left ventricular (LV) hypertrophy, increased myocardial oxygen demand, decreased coronary flow reserve, and heightened sensitivity to stressors such as new-onset arrhythmia, infection, acute coronary syndrome, and anemia that can precipitate acute decompensation.

Once decompensated, the ensuing ischemic cascade is self-reinforcing and results in end-organ hypoperfusion. Reduced forward flow across the stenotic valve triggers renin–angiotensin–aldosterone system activation, leading to vasoconstriction, reflex tachycardia, and increased afterload. These changes further elevate LV wall stress, compromise coronary perfusion pressure, and promote subendocardial ischemia, which impairs contractility and perpetuates shock.

BAV can temporarily interrupt this cycle by reducing the transvalvular gradient, lowering LV systolic pressure, and improving forward flow.¹³ These changes may permit short-term improvement, but hemodynamic benefits are transient and attenuate over weeks due to elastic recoil and restenosis. In contrast, urgent or emergent TAVR achieves definitive relief of outflow obstruction and rapid normalization of ventriculoarterial coupling^20,21 but requires more extensive procedural preparation, multidisciplinary team coordination, larger-bore access, and longer procedure time.

Synthesis of the Evidence

The studies reviewed here are observational; their designs, populations, and outcomes are summarized in Tables 1 and 2.

Table 1.

Studies comparing BAV and TAVR strategies in acute/emergent aortic stenosis

Study	Source	n	Comparison	Key finding	Limitation to applicability
Doma 202522	Meta-analysis	59,205	Emergent TAVR vs. BAV in emergent AS	30-d mortality relative risk 0.62 (95% CI 0.41–0.93) favoring emergent TAVR	Pooled observational data; no severity matching; same-admission BAV-TAVR not captured
Fujimoto 202423	Japan Registry	27,600	BAV-bridge vs. emergent TAVR in AS	In-hospital mortality: BAV-bridge 5.6% vs. emergent TAVR 1.3%	Includes TAVR in stable patients; excludes same-admission BAV-TAVR
Bandyopadhyay 202024	NIS 2011–2015	3464	Urgent BAV vs. urgent TAVR (propensity matched)	No mortality difference (OR 0.79, p = 0.29); TAVR had higher pacemaker, bleeding, and vascular complications	Noncontemporary data; excludes same-admission BAV-TAVR
Bongiovanni 201825	Multicenter cohort	141	Emergent TAVR vs. BAV-bridged TAVR in AVS with cardiogenic shock	30-d mortality: BAV-TAVR 15.6% vs. emergent TAVR 23.8%	Small sample; underpowered for subgroup analysis
Llah 202326	NIS 2016–2020	6970	TAVR vs. BAV in AS with cardiogenic shock	Composite event rate of 36.8% TAVR vs. 56.8% BAV	No shock severity stratification; confounding by indication

Abbreviations: AS, aortic stenosis; AVS, acute valve syndrome; BAV, balloon aortic valvuloplasty; NIS, National Inpatient Sample; OR, odds ratio; TAVR, transcatheter aortic valve replacement.

Table 2.

BAV-bridge outcomes, durability, timing, and reference data

Study	Design	No.	Analysis area	Key finding	Limitation to applicability
Kawsara 202027	NRD 2015–2016	3691	BAV bridging rate and bridged outcomes	38.6% bridged to TAVR; matched in-hospital mortality comparable to direct TAVR (3.5% vs. 3.7%, p = 0.91)	Excludes same-admission BAV-TAVR; no hemodynamic data; survival bias in bridged cohort
Nair 202428	Single-center cohort	199	Durability of BAV benefit without AVR	In-hospital mortality similar across treatments (p = 0.23); BAV-alone mortality ∼50% at 90 d without AVR	Single center; small sample; observational
Debry 201829	Multicenter cohort	44	Timing of BAV in AS-related cardiogenic shock	BAV within 48 h of inotrope initiation associated with improved survival	Small sample; no TAVR comparator; observational
Singh 201730	Global cVAD Registry	116	BAV + MCS (Impella) bridge outcomes	Planned Impella post-BAV; 1-y survival 56 vs. 29.2% emergent

Abbreviations: AS, aortic stenosis; AVR, aortic valve replacement; BAV, balloon aortic valvuloplasty; cVAD, catheter-based ventricular assist device; MCS, mechanical circulatory support; NRD, National Readmissions Database; TAVR, transcatheter aortic valve replacement.

Comparative Outcomes: BAV Versus Emergent TAVR

Large database analyses demonstrate lower overall mortality with emergent TAVR compared to BAV (Table 1). The largest meta-analysis (Doma et al.,²² n = 59,205) reported a 30-day mortality relative risk of 0.62 (95% CI 0.41–0.93) favoring direct TAVR. Fujimoto et al.²³ reported in-hospital mortality of 5.6% for BAV-bridge versus 1.3% for emergent TAVR in a Japanese registry of 27,600 emergent AS admissions. Llah et al.²⁶ found TAVR superior in the cardiogenic shock subgroup, with composite events of 36.8% versus 56.8% for BAV.

However, these comparisons are subject to confounding by indication. Patients often receive BAV because they cannot undergo an immediate TAVR. In studies that control for severity, the TAVR advantage narrows. Bandyopadhyay et al.²⁴ found no significant difference in propensity-matched in-hospital mortality between urgent BAV and urgent TAVR (odds ratio 0.79, 95% CI 0.51–1.21, p = 0.29), although TAVR was associated with higher rates of pacemaker requirement, bleeding, and vascular complications. Bongiovanni et al.²⁵ reported a more granular comparison in 141 AVS patients with cardiogenic shock, showing a numerically lower 30-day cardiovascular mortality of 15.6% in the BAV-bridged-TAVR group versus 23.8% in direct emergent TAVR. Although the comparison was underpowered and subject to confounding, it suggests that in the sickest AVS patients, a staged BAV-to-TAVR pathway may not carry the mortality penalty implied by unadjusted registry data.

Bridging Outcomes, Durability, and Timing

Among patients undergoing BAV with bridge intent (Table 2), Kawsara et al. examined 3691 BAV patients and found that 38.6% proceeded to TAVR, the majority of whom within 90 days. Among BAV-bridged-TAVR, propensity-matched in-hospital mortality was comparable to direct TAVR (3.5% vs. 3.7%, p = 0.91).²⁷

Nair et al. examined 199 patients with cardiogenic shock due to severe AS. In-hospital mortality was similar across BAV, TAVR, and surgical AVR, but the early benefit of BAV was not durable in the absence of definitive AVR. Mortality after BAV alone approached 50% by 90 days, underscoring its temporizing role.²⁸

Two key findings within the literature inform the therapeutic window for timing of AVR. Debry et al.²⁹ demonstrated that BAV performed within 48 hours of inotrope initiation was associated with improved survival compared to delayed BAV in patients with AS-related cardiogenic shock. McKenna et al.³¹ identified that each 5-day delay to TAVR after acute decompensation was associated with an additional 9% increased risk of heart failure hospitalization or death.

Emerging Approaches

Mechanical circulatory support (MCS) combined with BAV has been proposed as a stabilization strategy for the most critically ill AVS patients, but the evidence base is fairly limited. Singh et al. examined 116 patients with severe AS who underwent BAV followed by planned Impella placement in the Global catheter-based ventricular assist device (cVAD) registry. Patients receiving planned Impella after BAV demonstrated 1-year survival of 56% versus 29.2% in those with emergent Impella placement, despite comparable Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) scores.³⁰ Notably, subsequent definitive AVR is a confounding variable, as outcomes within this high-risk patient population are likely influenced more by definitive valve replacement than by specific MCS modality or timing. Additional case literature outlines the potential roles of venoarterial extracorporeal membrane oxygenation (VA-ECMO) and other MCS modalities in improving AVS patient outcomes.32, 33, 34, 35

Limitations of Current Evidence

The comparative effectiveness evidence for BAV-bridge versus emergent TAVR rests on limited analyses. Key limitations span all evidence levels (Figure 1).

Figure 1.

Key limitations of comparative evidence: BAV-bridge vs. emergent TAVR. Summary of methodological limitations precluding comparison of BAV-bridge and emergent TAVR in acute valve syndrome, organized by 3 domains: study design, hemodynamic phenotyping, and outcome reporting.

Abbreviations: BAV, balloon aortic valvuloplasty; TAVR, transcatheter aortic valve replacement.

Collectively, these limitations preclude a definitive comparison between direct urgent/emergent TAVR and BAV-bridge strategies. Existing data are insufficient to define the severity threshold at which immediate TAVR becomes unsafe or BAV-bridge becomes beneficial.

Clinical Frameworks for Severity Assessment

Acute Valve Syndrome Classification

In the Egnite multicenter registry of 17,838 patients with severe AS undergoing inpatient AVR, Généreux et al.³⁶ classified presentations as asymptomatic (14%), progressive valve syndrome (34.3%), and AVS (51.7%). AVS was associated with more than twofold increase in short- and long-term mortality compared to non-AVS patients. Subsequent literature has characterized AVS patients as showing a physiologic profile reflective of end-organ hypoperfusion, with serum lactate, creatinine, and liver transaminases effectively stratifying mortality risk.³⁷

Secondary analysis of the EARLY TAVR trial reinforces these findings. Among surveilled patients, approximately 40% presented with AVS, experiencing significantly higher rates of death, stroke, or heart failure hospitalization compared to patients receiving early TAVR (adjusted hazard ratio 2.12, 95% CI 1.19–3.78).¹⁹

Cardiac Damage Staging

The cardiac damage staging system proposed by Généreux et al.^38,39 characterizes patients from stage 0 (no extravalvular damage) to stage 4 (right-sided failure with severe tricuspid regurgitation) based on pre-AVR echocardiography. A meta-analysis including 21,876 AS patients confirmed a stepwise increase in all-cause mortality with advancing cardiac damage staging.⁴⁰

In AVS, cardiac damage staging may provide prognostic context and improve estimation of the patient’s likelihood for recovery. Lower cardiac damage stages are suggestive of retained RV function and may be more likely to respond favorably to BAV. Patients with high cardiac damage (stage 3–4) often have RV dysfunction, tricuspid regurgitation, and pulmonary hypertension. In these patients, BAV may serve as a therapeutic trial, with significant hemodynamic improvement suggesting reversibility in support of TAVR candidacy.

More recently, Tomaselli et al.⁴¹ proposed a strain-based, multichamber cardiac damage model incorporating LV global longitudinal strain, peak atrial longitudinal strain, and RV free-wall strain, which may capture subclinical dysfunction beyond conventional markers.

SCAI Shock Classification

The Society for Cardiovascular Angiography and Interventions (SCAI) shock classification provides a validated framework for cardiogenic shock severity from stage A (at risk) to stage E (extremis), with stepwise mortality risk validated across diverse shock etiologies.42, 43, 44

Stage A encompasses hemodynamically stable patients at risk for shock development, stage B represents early hemodynamic instability without hypoperfusion, stage C (“classic shock”) denotes hypoperfusion requiring pharmacologic or mechanical intervention, stage D indicates deterioration despite initial therapy, and stage E represents refractory shock with actual or impending circulatory collapse. Patients presenting in stages C through E represent the population in whom immediate TAVR may be infeasible and for whom BAV-bridge strategies may offer the greatest benefit.

Integrated Assessment

Effective management of AVS may involve consideration of the patient’s acuity, hemodynamic instability, and cumulative cardiac damage. Within the Graphical Abstract, SCAI stage, cardiac damage stage, and presentation acuity are plotted together alongside treatment considerations overlaid.

Management Considerations

The current evidence base does not support a validated clinical algorithm. The following discussion reflects consensus-based reasoning informed by available observational data. These considerations should be interpreted as requiring prospective validation rather than established clinical recommendations (Figure 2A and B).

Figure 2.

(a) Initial assessment and treatment pathway selection. Proposed algorithm for initial evaluation of patients presenting with severe AS with AVS. Patients stable for preprocedural workup proceed to expedited TAVR. Unstable patients are stratified by SCAI shock stage. (b) Post-BAV management and TAVR timing. Proposed algorithm for management following BAV.

Abbreviations: AS, aortic stenosis; AVS, acute valve syndrome; BAV, balloon aortic valvuloplasty; CTA, computed tomography angiography; MCS, mechanical circulatory support; SCAI, Society for Cardiovascular Angiography and Interventions; TAVR, transcatheter aortic valve replacement.

Step 1: Assess Stability and Shock Severity

The decision to pursue BAV-bridge versus emergent TAVR requires consideration of the risk of acute hemodynamic collapse alongside the patient's underlying physiological reserve. Initial evaluation should address whether the patient can tolerate urgent TAVR workup (Figure 2A).

SCAI Stage A–SCAI Stage B (Stable/At-Risk)

Patients who are stable enough to complete anatomic planning should generally proceed through an expedited TAVR pathway, with close reassessment for deterioration.

SCAI Stage C–SCAI Stage D (Classic/Deteriorating Shock)

In patients with escalating support needs, immediate TAVR feasibility should be assessed alongside cardiac damage stage and end-organ trajectory. When standard TAVR planning is unsafe or impractical, BAV may offer the opportunity to stabilize patient hemodynamics and enable semielective TAVR. In patients with higher overall cardiac damage, BAV may be used as a therapeutic trial, with hemodynamic improvement suggestive of reversibility in support of TAVR candidacy.

SCAI Stage E (Extremis)

Goals-of-care discussion is paramount, with consideration of BAV ± MCS in patients with rapid-onset decompensation. BAV may also be considered for palliation within this patient population.

Step 2: Evaluation for Urgent/Emergent TAVR

These are steps to follow for TAVR workup candidates:

• •Assess the need for transfer to a TAVR-capable center. If a transfer is unsafe, proceed with BAV and plan the transfer after hemodynamic stabilization.
• •Evaluate stability for TAVR protocol computed tomography angiography (CTA). When CTA is infeasible, proceed with BAV and modified preprocedural planning.

Additional TAVR Planning Considerations

Modified preprocedural planning can be initiated at the time of BAV for patients who cannot safely undergo TAVR protocol CTA.

• •Iliofemoral angiography: Distal aortogram with bilateral iliac and femoral arteriography assesses vessel caliber, tortuosity, and calcification burden.⁴⁵
• •Intravascular ultrasound (IVUS): IVUS provides cross-sectional imaging with reasonable correlation to CT-derived minimum luminal diameter measurements. IVUS-measured diameters are consistently larger than CTA measurements, potentially identifying patients suitable for large-bore access who might otherwise be excluded by CT alone. The combined angiography/IVUS approach offers substantially reduced contrast utilization (29 vs. 100 mL; p < 0.001) and radiation exposure compared to CTA.⁴⁵

Step 3: Perform BAV With Hemodynamic Monitoring

Conservative BAV Approach for Emergent Cases

For patients presenting in cardiogenic shock without prior CT-based annular sizing, echocardiographic data may guide BAV balloon sizing. Although no data define an optimal BAV endpoint, a reasonable target is at least 50% reduction in the LV–aorta (Ao) gradient and/or nonsevere range post-BAV gradients.¹³ Ideally, concomitant right heart catheterization should be performed to measure pre-BAV and post-BAV cardiac output and filling pressures.

A conservative strategy minimizes procedural risk while preserving options for subsequent MCS placement.

• •Balloon sizing: Size to LV outflow tract diameter on transthoracic echocardiography. Standard practice is to size at a maximum of 1:1 from average LV outflow tract diameter on CT, or ≤2.0 mm over transthoracic echocardiography/transesophageal echocardiography diameter.¹³ A 20 mm starting size is appropriate for most patients and provides meaningful gradient reduction while minimizing aortic regurgitation risk.
• •Ventricular pacing: Omission of rapid ventricular pacing during balloon inflation may be considered in patients with RV dysfunction or severe LV dysfunction. A longer balloon (such as 5–6 cm) may improve stability during inflation. Pacing may also be omitted with nonocclusive balloon systems (e.g. True Flow), though these require larger access sheaths (e.g. 16F).⁴⁶
• •Semicompliant balloon selection: Low-profile semicompliant balloons require only 8–10F sheaths, enabling BAV at the time of coronary angiography without large-bore access. This approach is advantageous in shock patients requiring concomitant coronary assessment with reduced bleeding risk in patients with coagulopathy.

Post-BAV Evaluation Protocol

Comprehensive postprocedural evaluation should include the steps outlined in Figure 2B:

• 1.Hemodynamic assessment: Document gradient reduction and hemodynamic response. Most patients improve hemodynamically after gradient reduction. Those who fail to improve following BAV should be considered for MCS.
• 2.AR evaluation: Assess via aortography and/or echocardiography. This assessment is critical for subsequent MCS device selection.

Acute Aortic Regurgitation After BAV

Severe acute AR complicates approximately 1.3% of BAV procedures (95% CI 0.91%–1.78%; 13 studies, 5289 patients).¹³ Moderate-to-severe AR represents an absolute contraindication to the intraaortic balloon pump.⁴⁷

Step 4: Selection of MCS Modality

Each MCS modality has distinct effects in fixed LV outflow obstruction (Table 3). Selection depends on shock severity, hemodynamic goals, post-BAV AR status, and vascular access. For patients in advanced SCAI stages, consider emergent BAV with MCS support (Impella or VA-ECMO with LV unloading) followed by AVR at the earliest safely achievable time. The risk of iatrogenic AR after BAV should be considered prior to proceeding in patients likely to require VA-ECMO. Early goals-of-care discussions and consideration of palliation options are essential.^50,51

Table 3.

MCS selection in severe aortic stenosis

Device	Mechanism	AS-specific advantage	AS-specific limitation	Potential role in AVS
IABP	Aortic counterpulsation with diastolic inflation and systolic deflation	Increases diastolic coronary perfusion without crossing stenotic valve	Provides limited cardiac output augmentation; moderate AR is a contraindication	Low-intensity support as a temporizing measure; no survival benefit in RCTs (IABP-SHOCK II)48,49; avoid if post-BAV AR develops
Impella	Transvalvular microaxial pump: withdraws blood from LV and ejects into ascending aorta	Provides direct LV unloading and forward flow across the valve	Severe AS and calcification can make valve crossing difficult; moderate to severe AR is a contraindication	May be considered after BAV in carefully selected patients when valve crossing is feasible and AR is absent or mild; notably, the evidence base is relatively limited50,51
VA-ECMO	Peripheral VA-ECMO: drains venous blood and returns oxygenated blood to the arterial system	Rapidly restores systemic perfusion; support is not dependent on crossing the stenotic valve	Increases LV afterload through retrograde aortic flow and may worsen LV distension	High-intensity support; requires planned LV unloading; AR is contraindication without LV vent

Abbreviations: AR, aortic regurgitation; AS, aortic stenosis; AVS, acute valve syndrome; BAV, balloon aortic valvuloplasty; IABP, intraaortic balloon pump; LV, left ventricle; MCS, mechanical circulatory support; RCT, randomized controlled trial; VA-ECMO, venoarterial extracorporeal membrane oxygenation.

Clinical Vignette

An 82-year-old woman with known severe AS (valve area 0.7 cm², mean gradient 48 mmHg, peak velocity 5.0 m/s) presents to the emergency department with cardiogenic pulmonary edema and hypoxemic respiratory failure. Despite diuresis and noninvasive positive pressure ventilation, her condition worsens, and she develops progressive hypotension requiring norepinephrine infusion. Serum lactic acid rises from 2.1 to 5.8 mmol/L over 4 hours. Stat echocardiography confirms severe AS with a new reduction in LV ejection fraction from 60 to 35%. Her creatinine has increased from baseline 1.2 to 2.8 mg/dL. The heart team faces a critical decision: Can this patient safely undergo emergent TAVR workup and implantation, or does she first require BAV for hemodynamic stabilization? This clinical scenario, repeated daily in structural heart programs worldwide, exemplifies the central challenge of deciding between emergent TAVR or BAV bridge therapy in critical AVS patients.

Within the proposed framework, her presentation is classified as SCAI stage C–D, with rising lactate, vasopressor dependence, and acute kidney injury. She is not stable for comprehensive TAVR evaluation because of progressive hemodynamic instability and worsening renal dysfunction. The heart team proceeds with emergent BAV. Following BAV with a 50% gradient reduction, lactate begins to clear, and vasopressor requirements decline. Over the next 48 hours, renal function improves, and she is weaned from vasopressors. With hemodynamic stabilization, she undergoes TAVR-protocol CTA and proceeds to definitive TAVR during the same hospitalization once anatomic planning is complete. This scenario illustrates the potential role of BAV as a bridge-to-definitive AVR in selected AVS patients with recoverable shock physiology.

Future Directions

Further prospective research is required to improve delineation of optimal practice in AVS patients. A multicenter registry collecting SCAI shock stage, cardiac damage stage, hemodynamic parameters, MCS utilization, and BAV-to-TAVR outcomes would improve severity-matched comparisons, as these current comparisons remain largely infeasible with existing registry data.

Limitations

This narrative review did not use systematic search or meta-analysis; formal pooling would be inaccurate given that existing literature largely does not match for AS severity and incorporate the indication for procedure type (e.g., palliative BAV). Our proposed framework represents synthesis of available evidence and mechanistic reasoning rather than a prospectively validated decision tool. Rapid evolution of TAVR technology, MCS devices, and heart team infrastructure may further limit applicability of older studies to contemporary practice.

Conclusion

Once abandoned as definitive therapy, BAV retains a contemporary role as a temporizing strategy in selected AVS patients who cannot undergo immediate valve replacement. Current evidence favors urgent/emergent TAVR when anatomic planning, vascular access, and procedural logistics are feasible, but comparisons with BAV are confounded by patient selection and treatment intent. Effective AVS management should integrate acute hemodynamic status, cardiac damage, anatomic feasibility, post-BAV response, and goals of care. Prospective data are needed to validate severity-based frameworks and define the patients most likely to benefit from BAV-bridge versus direct urgent TAVR.

Ethics Statement

The review reported has adhered to all relevant ethical guidelines.

Funding

The authors have no funding to report.

Disclosure Statement

Raymond L. Benza receives speaking, consulting, and proctoring income from Abbott. Deepak R. Talreja receives speaking, consulting, and proctoring income from Medtronic, Abbott, Abiomed, Bristol Myers Squibb, Novartis, and Amgen. Matthew R. Summers receives speaking, consulting, and proctoring income from Abbott Pharmaceuticals and Medtronic and serves on the advisory board for Abbott Pharmaceuticals, Medtronic, Picardia, Shockwave, DASI, and Abiomed.

The other authors had no conflicts to declare.