Double-Chambered Right Ventricle (DCRV) #2: Surgical Repair

Double-chambered right ventricle (DCRV) is a progressive form of intracavitary right ventricular (RV) obstruction produced by anomalous hypertrophied or fibromuscular bundles that separate a proximal high-pressure chamber from a distal low-pressure chamber. Definitive treatment is surgical division and resection of the obstructing tissue, with correction of associated lesions—most often a ventricular septal defect (VSD)—during the same operation. The objective is not indiscriminate “RVOT muscle resection,” but restoration of a widely patent pathway from the RV inflow and sinus to the infundibulum while preserving the tricuspid apparatus, normal septomarginal architecture, conduction tissue, pulmonary valve, and RV function [1,2].

For the underlying morphology and pressure relationships, see Double-Chambered Right Ventricle (DCRV) #1: Anatomy. The regional relationship between the septomarginal trabeculation, moderator band, papillary muscles, and right bundle branch is reviewed in RV Muscle Bands and the Conduction Axis.

1. Indications and Timing

Because the obstruction can progress, operative timing should integrate symptoms, serial gradient, proximal RV pressure, RV hypertrophy or dysfunction, associated lesions, and the anticipated consequences of continued pressure loading. Symptoms attributable to DCRV include exertional dyspnea, fatigue, exercise limitation, chest discomfort, syncope, and right-sided heart failure. Surgery is appropriate for symptomatic patients with clinically important intracavitary obstruction and for patients with progressive obstruction or substantial proximal RV pressure loading, even when symptoms are limited [2–4].

A single Doppler peak gradient should not be used in isolation. Maximum instantaneous Doppler gradients may overestimate catheter peak-to-peak gradients, and the measured value depends on flow, alignment, and the precise level sampled. Historical series have used different gradient thresholds, and pediatric operative criteria are not standardized. The current 2025 ACC/AHA/HRS/ISACHD/SCAI adult congenital guideline recommends repair for adults with moderate or greater DCRV obstruction and otherwise unexplained heart-failure symptoms, cyanosis, or exercise limitation; repair is also reasonable in asymptomatic adults with severe obstruction to prevent symptoms and adverse RV remodeling [3].

Earlier intervention is favored when serial imaging shows increasing obstruction, when proximal RV pressure is approaching systemic levels, or when a VSD, subaortic membrane, aortic valve prolapse/regurgitation, or another lesion already warrants operation. Observation can be reasonable for a truly mild, stable, asymptomatic gradient with normal RV size and function, but surveillance must recognize that DCRV is a progressive substrate rather than a reliably static muscle bundle [2,4].

2. Preoperative Anatomical Map

The operative plan should be based on a three-dimensional map of the obstruction rather than on the label “RVOT stenosis.” Echocardiography should define:

• The proximal and distal RV chambers.
• The location, length, and attachments of the obstructing bundles.
• The narrowest intracavitary orifice and the point where Doppler acceleration begins.
• The relationship of the obstruction to the tricuspid valve, moderator band, septomarginal trabeculation, papillary muscles, infundibulum, and pulmonary valve.
• VSD type, size, shunt direction, and communication with the proximal or distal chamber.
• Pulmonary annular, valvar, main pulmonary artery (MPA), and branch pulmonary artery anatomy.
• Associated subaortic stenosis, aortic cusp prolapse or regurgitation, tricuspid regurgitation, and other congenital lesions.

Cardiac magnetic resonance or computed tomography can supplement echocardiography when transthoracic windows are limited, particularly in older patients or after previous surgery. Catheterization is not routinely required solely to diagnose DCRV, but pullback pressures from the pulmonary artery through the distal and proximal RV can clarify discordant noninvasive data or associated hemodynamic questions.

3. Operative Exposure and Cardiopulmonary Bypass

Repair is generally performed through median sternotomy with cardiopulmonary bypass and cardioplegic arrest. Bicaval cannulation facilitates right atriotomy and exposure through the tricuspid valve. Before bypass, the surgeon should inspect the epicardial RV and pulmonary arteries, recognizing that the intracavitary obstruction may not correspond to an obvious external narrowing.

After right atriotomy, the tricuspid valve is retracted gently to expose the VSD, septal surface, and obstructing muscular partition. Retraction must avoid chordal distortion or injury to the anterior and septal leaflets. A transverse pulmonary arteriotomy can provide a complementary distal view through the pulmonary valve, helping define the upper margin of the obstruction and confirm that the distal infundibulum and pulmonary valve are free of additional stenosis. Historical series established that a combined transatrial–transpulmonary approach can provide complete exposure while avoiding a right ventriculotomy in most patients [5,6].

4. Resection of the Obstructing Muscle Bundles

Resection begins by identifying the true obstructing partition and the residual opening between the proximal and distal chambers. The surgeon should distinguish pathological septoparietal bundles from normal structures, including the moderator band, septomarginal trabeculation, papillary-muscle attachments, and muscular infundibulum. The goal is to enlarge the functional pathway sufficiently while preserving normal RV geometry.

A practical sequence is:

1. Define the proximal edge of the obstructing bundle through the tricuspid valve.
2. Identify the distal margin directly or through the pulmonary arteriotomy.
3. Divide the dominant bridging bundle under direct vision.
4. Resect additional hypertrophied septal and parietal muscle in controlled increments.
5. Reassess the pathway repeatedly with a right-angle instrument, dilator, or direct visualization from both directions.
6. Confirm that no discrete residual shelf remains and that the pulmonary valve and infundibulum are unobstructed.

Incremental resection is safer than a single deep excision. Excessively deep septal resection can injure the conduction system or create a VSD; aggressive free-wall resection can damage papillary-muscle or chordal attachments, produce RV dysfunction, or cause bleeding. The right bundle branch courses within the septomarginal/moderator-band complex, so indiscriminate division of recognizable normal muscle is inappropriate. Complete heart block is uncommon, but right bundle branch block may occur, particularly when muscle resection is combined with closure of a perimembranous VSD [5,7].

5. Choice of Surgical Approach

Transatrial approach

The transatrial route is preferred when the obstruction and associated VSD are adequately visible through the tricuspid valve. It avoids an RV scar and preserves RV free-wall mechanics. In a 73-patient cohort, 61 of 69 repairs were completed transatrially and only eight required an additional ventriculotomy; there was no hospital or late mortality, and no early progression of the residual gradient [2].

Combined transatrial–transpulmonary approach

This approach provides proximal and distal visualization without crossing the RV free wall. It is particularly useful when the superior limit of the bundle is difficult to define through the tricuspid valve. In early comparative experience, patients repaired without ventriculotomy had excellent gradient relief and less postoperative inotropic requirement than those undergoing a classical right ventriculotomy, although the series was small and nonrandomized [5].

Transventricular approach

A limited right ventriculotomy remains appropriate when severe hypertrophy, a long or low obstructing tunnel, abnormal orientation, previous repair, or inadequate transatrial/transpulmonary exposure prevents safe complete resection. The incision should be placed in the distal low-pressure chamber and oriented to minimize coronary and RV free-wall injury. Ventriculotomy is therefore a selective exposure strategy, not evidence of an incomplete transatrial operation. Adult series demonstrate satisfactory results with transatrial, combined, and transventricular approaches when selected according to anatomy [7,8].

6. Management of the Ventricular Septal Defect and Associated Lesions

The VSD should be inspected after partial muscle-bundle resection because hypertrophied tissue may obscure its true margins. Most DCRV-associated defects are perimembranous, but outlet, muscular, and spontaneously restricted defects also occur. A hemodynamically important or surgically exposed VSD is closed with a patch or, in selected small defects, direct sutures. Sutures along the posteroinferior rim of a perimembranous VSD should remain superficial and respect the expected course of the atrioventricular conduction axis.

Associated subaortic membrane should be resected during the same operation. Aortic cusp prolapse and regurgitation require careful assessment because VSD closure alone may not address established cusp deformation. The tricuspid valve should be reassessed after retraction and VSD patch placement; repair is indicated if leaflet or chordal injury, annular dilation, or clinically important regurgitation is present.

7. When Is Patch Augmentation Needed?

Patch augmentation is not routine for isolated DCRV. Adequate muscle resection usually relieves the obstruction without enlargement of the pulmonary annulus or RV free wall. An RVOT patch may be required when there is residual fixed narrowing, a hypoplastic distal infundibulum or pulmonary annulus, an associated pulmonary stenosis, or when a necessary ventriculotomy cannot be closed without recreating obstruction.

An MPA patch should be reserved for a discrete MPA abnormality, restrictive pulmonary arteriotomy closure, or associated supravalvar obstruction. Enlarging the MPA alone cannot relieve a mid-RV intracavitary obstruction. When patching is necessary, the reconstruction should produce a smooth outflow pathway without pulmonary-valve distortion, aneurysmal enlargement, or branch pulmonary artery distortion.

8. Intraoperative Assessment

After separation from bypass, transesophageal or epicardial echocardiography should assess:

• Residual intracavitary peak and mean gradients.
• The exact level of any residual acceleration.
• Proximal RV pressure and global/regional RV function.
• Residual VSD or patch leak.
• Tricuspid valve competence.
• Pulmonary valve function and RVOT/MPA geometry.
• Aortic valve function and residual LVOT obstruction when relevant.

A small residual dynamic gradient may decline as hypertrophy regresses, whereas a discrete residual jet at the original partition suggests incomplete resection. Direct pressure measurements in the proximal RV, distal RV, and pulmonary artery are useful when imaging is uncertain or the postoperative RV pressure remains unexpectedly high.

9. Early Postoperative Management and Complications

The postoperative course is usually straightforward after complete repair. Management focuses on RV preload, contractility, rhythm, and pulmonary vascular resistance. Important early concerns include residual obstruction, RV dysfunction after extensive resection or ventriculotomy, bleeding from deep muscle excision, VSD patch leak, tricuspid regurgitation, right bundle branch block, complete heart block, and ventricular arrhythmia.

A new high RV pressure should prompt differentiation among residual intracavitary obstruction, pulmonary valvar or arterial obstruction, elevated pulmonary vascular resistance, and Doppler overestimation. Persistent low cardiac output after an extensive ventriculotomy may reflect impaired RV mechanics rather than residual obstruction alone.

10. Outcomes and Long-Term Surveillance

Published evidence consists predominantly of retrospective single-center series, but results are consistently favorable. In 40 patients followed for a mean of 16.5 years, Hachiro and colleagues reported no hospital or late deaths and no reoperation for recurrent RV obstruction [9]. A 35-patient cohort likewise reported no early or late deaths and no reoperation for obstruction over a median seven-year follow-up [10]. Among 38 operated patients, including 29 with long-term echocardiographic data, Amano and colleagues found no death, reintervention, or DCRV recurrence over a mean 11 years [11].

More contemporary pediatric data are similar. In 89 patients, the mean echocardiographic gradient decreased from 66.3 mmHg preoperatively to 11.8 mmHg immediately and 10.4 mmHg at late follow-up; reinterventions addressed residual VSD, residual pulmonary stenosis, or severe tricuspid regurgitation rather than recurrent DCRV [12]. A 2023 series of 64 patients showed a reduction from 62.3 to 15.7 mmHg without hospital mortality at a mean follow-up of approximately 47 months [13].

Surveillance remains lifelong. Follow-up echocardiography should assess residual or recurrent intracavitary gradient, RV size and function, tricuspid and pulmonary valve function, residual VSD, aortic regurgitation, and subaortic obstruction. Primary DCRV rarely recurs after adequate resection, but postoperative DCRV after tetralogy of Fallot repair is a distinct substrate: one 17-patient series reported recurrent obstruction in three patients, supporting closer gradient surveillance in this group [14]. In adolescents and adults, exercise capacity and rhythm surveillance are appropriate when symptoms, ventricular dysfunction, surgical scar, or prior arrhythmia warrants them.

Key Surgical Principles

• Resect the pathological intracavitary partition sufficiently to connect the proximal RV with the distal infundibulum.
• Prefer transatrial or combined transatrial–transpulmonary exposure when anatomy permits.
• Use right ventriculotomy selectively when complete and safe resection cannot otherwise be achieved.
• Preserve the tricuspid apparatus, septomarginal/moderator-band architecture, conduction tissue, pulmonary valve, and RV free wall.
• Close significant associated VSDs and address subaortic or valvar lesions during the same operation.
• Add an RVOT patch only for residual fixed narrowing or associated outflow hypoplasia; an MPA patch treats MPA-level disease, not the primary intracavitary obstruction.
• Confirm the result anatomically and hemodynamically before leaving the operating room.

References

[1] Loukas M, Housman B, Blaak C, Kralovic S, Tubbs RS, Anderson RH. Double-chambered right ventricle: a review. Cardiovasc Pathol. 2013;22(6):417-423. doi:10.1016/j.carpath.2013.03.004.

[2] Galal O, Al-Halees Z, Solymar L, et al. Double-chambered right ventricle in 73 patients: spectrum of the disease and surgical results of transatrial repair. Can J Cardiol. 2000;16(2):167-174. PMID:10694587.

[3] Gurvitz M, Krieger EV, Fuller S, et al. 2025 ACC/AHA/HRS/ISACHD/SCAI Guideline for the Management of Adults With Congenital Heart Disease. Circulation. Published online December 18, 2025. doi:10.1161/CIR.0000000000001402.

[4] Kahr PC, Alonso-Gonzalez R, Kempny A, et al. Long-term natural history and postoperative outcome of double-chambered right ventricle: experience from two tertiary adult congenital heart centres and review of the literature. Int J Cardiol. 2014;174(3):662-668. doi:10.1016/j.ijcard.2014.04.177.

[5] Penkoske PA, Duncan N, Collins-Nakai RL. Surgical repair of double-chambered right ventricle with or without ventriculotomy. J Thorac Cardiovasc Surg. 1987;93(3):385-393. doi:10.1016/S0022-5223(19)36416-5.

[6] Cabrera A, Martinez P, Rumoroso J, et al. Double-chambered right ventricle. Eur Heart J. 1995;16(5):682-686. doi:10.1093/oxfordjournals.eurheartj.a060973.

[7] Said SM, Burkhart HM, Dearani JA, O'Leary PW, Ammash NM, Schaff HV. Outcomes of surgical repair of double-chambered right ventricle. Ann Thorac Surg. 2012;93(1):197-200. doi:10.1016/j.athoracsur.2011.08.043.

[8] Kottayil BP, Dharan BS, Pillai VV, et al. Surgical repair of double-chambered right ventricle in adulthood. Asian Cardiovasc Thorac Ann. 2011;19(1):57-60. doi:10.1177/0218492310395955.

[9] Hachiro Y, Takagi N, Koyanagi T, Morikawa M, Abe T. Repair of double-chambered right ventricle: surgical results and long-term follow-up. Ann Thorac Surg. 2001;72(5):1520-1522. doi:10.1016/S0003-4975(01)02982-4.

[10] Telagh R, Alexi-Meskishvili V, Hetzer R, Lange PE, Berger F, Abdul-Khaliq H. Initial clinical manifestations and mid- and long-term results after surgical repair of double-chambered right ventricle in children and adults. Cardiol Young. 2008;18(3):268-274. doi:10.1017/S1047951108001984.

[11] Amano M, Izumi C, Hayama Y, et al. Surgical outcomes and postoperative prognosis beyond 10 years for double-chambered right ventricle. Am J Cardiol. 2015;116(9):1431-1435. doi:10.1016/j.amjcard.2015.07.069.

[12] Surucu M, Erdoğan İ, Varan B, Özkan M, Tokel N, Aşlamacı S. Early and late outcomes of surgical repair of double-chambered right ventricle: a single-centre experience. Cardiol Young. 2020;30(3):409-412. doi:10.1017/S1047951120000244.

[13] Halder V, Ghosh S, Thingnam SKS, et al. Early and mid-term outcomes of double-chambered right ventricle repair: an 8-year experience. Cardiol Young. 2024;34(2):268-271. doi:10.1017/S1047951123001531.

[14] Moran AM, Hornberger LK, Jonas RA, Keane JF. Development of a double-chambered right ventricle after repair of tetralogy of Fallot. J Am Coll Cardiol. 1998;31(5):1127-1133. doi:10.1016/S0735-1097(98)00034-5.