Abstract
Lymphocytic fulminant myocarditis results in severe myocardial damage that is irreversible in some patients. In these patients, mechanical circulatory support, as the main treatment, is difficult. We describe a patient with a myocarditis-associated arrested heart who underwent successful left ventricular assist device implantation and extracardiac total cavopulmonary connection (EC-TCPC). EC-TCPC was chosen after fluid dynamics simulation was performed using computational fluid dynamics analysis of blood flow. In the analysis, EC-TCPC was compared with the Glenn procedure and the classic Fontan procedure; EC-TCPC had the best performance.
Myocardial injury after lymphocytic fulminant myocarditis is reversible in 60% to 80% of patients and has a good prognosis with appropriate mechanical circulatory support.1 However, mechanical circulatory support is challenging in patients with irreversible myocardial damage with poor biventricular function. Total artificial heart and biventricular assist device (BiVAD) implantation are options; however, these treatments are not approved in Japan. Although a combined durable left ventricular assist device (LVAD) and extracorporeal right ventricular assist device (RVAD) provides better hemodynamic support, this approach requires hospitalization until transplantation. We report a case of myocarditis-associated arrested heart successfully supported by an LVAD with extracardiac total cavopulmonary connection (EC-TCPC).
A 24-year-old man with fever and malaise for 4 days presented with cardiogenic shock necessitating an Impella CP SmartAssist (Abiomed) and venoarterial extracorporeal membrane oxygenation. Multiorgan function deteriorated within 2 days, and complete atrioventricular block developed. Therefore, extracorporeal BiVAD implantation was performed.
Electrocardiography revealed repeated asystole and complete atrioventricular block with no recovery to regular rhythm. However, end-organ perfusion was well maintained under BiVAD support for 3 months. Subsequently, a HeartMate3 (Abbott Laboratories) was implanted with an extracorporeal RVAD. A subsequent right-sided heart catheterization study revealed the following: pulmonary artery wedge pressure (PAWP), 6 mm Hg; main pulmonary artery (PA), 12 mm Hg; right atrium, 13 mm Hg; and mixed venous oxygen saturation (Svo2), 56.4% (HeartMate3: 4.6 L; off RVAD). The calculated pulmonary vascular resistance was 0.8 Wood unit.
We considered that bypassing the right ventricle (RV) would improve the hemodynamics of the pulmonary circulation under cardiac arrest settings, allowing the patient to return to living at home.2,3 We performed hemodynamic simulation surgery to compare EC-TCPC (Figure 1A) with the normal anatomy of the right-sided heart system (Figure 1B), Glenn procedure (Figure 1C), and classic Fontan procedure (Figure 1D) using computational fluid dynamics analysis. We used the system provided by Cardio Flow Design with a previously described computational fluid dynamics method.4 During simulation, the energy loss of EC-TCPC was 1.53 mW/s, which was lower than that of the normal anatomy of the right-sided heart system (3.1 mW/s), Glenn procedure (1.79 mW/s), and classic Fontan procedure (3.37 mW/s). The flow dynamics (streamline) study demonstrated that the Glenn procedure caused considerably imbalanced blood flow between the left and right PAs. Therefore, we chose EC-TCPC.
Figure 1.
Computational fluid dynamics analysis for each surgical technique showing streamline flow (left) and energy loss (right). Blue indicates blood flow from the superior vena cava (SVC); red, blood flow from the inferior vena cava (IVC). (A) Extracardiac total cavopulmonary connection. (B) Normal anatomy of right-sided heart system. (C) Glenn procedure. (D) Classic Fontan procedure. (IVC, inferior vena cava; SVC, superior vena cava.)
After cardiopulmonary bypass was induced, the main PA was incised and divided. The interatrial septum was completely resected, the tricuspid valve leaflet was removed, and the RV cavity was suture plicated internally. The superior vena cava was incised and directly anastomosed to the right PA. We then created an EC-TCPC pathway using 22 mm of expanded polytetrafluoroethylene graft from the dissected inferior vena cava to the right PA (Figure 2A). The patient was weaned from cardiopulmonary bypass under nitric oxide inhalation (20 ppm). The patient was then returned to the intensive care unit at HeartMate3 settings of 5.0 L/min and 6000 rpm. He was weaned from mechanical ventilation 6 hours later and transferred to the general ward on postoperative day 7.
Figure 2.
(A) Schema of surgical procedures. (B) Postoperative enhanced computed tomography. (ASD, atrial septal defect; EDV, end-diastolic volume; ePTFE, expanded polytetrafluoroethylene; IVC, inferior vena cava; IVSd, interventricular septal thickness end diastole; LVd Mass, left ventricular mass; LVIDd, left ventricular internal dimension in diastole; LVPWd, left ventricular posterior wall end diastole; PA, pulmonary artery; RPA, right pulmonary artery; RV, right ventricle; RWT, relative wall thickness; SVC, superior vena cava.)
On postoperative day 30, a right-sided heart catheterization study revealed the following: PAWP, 5 mm Hg; superior and inferior vena cava, 11 mm Hg; left PA, 10 mm Hg; and Svo2, 68% (HeartMate3: 4.2 L/min, 5800 rpm). The arterial partial pressure of oxygen was 72 mm Hg (room air). Contrast-enhanced computed tomography confirmed an excellent EC-TCPC pathway (Figure 2B). Ten months after EC-TCPC, a right-sided heart catheterization study revealed the following: PAWP, 2 mm Hg; inferior vena cava, 11 mm Hg; and Svo2, 67% (HeartMate3: 4.3 L/min, 5800 rpm). Echocardiography revealed a sufficient left ventricle size of 64 mm (Figure 3). No neurologic deficits or pump-related complications occurred for 11 months postoperatively.
Figure 3.
Echocardiography (A) before and (B) after extracardiac total cavopulmonary connection operation (EDV, end-diastolic volume; IVSd, interventricular septal thickness end diastole; LVd Mass, left ventricular mass; LVIDd, left ventricular internal dimension in diastole; LVPWd, left ventricular posterior wall end diastole; RWT, relative wall thickness).
Comment
The reported 6-month survival of patients with a ventricular assist device for stage 3 single-ventricle congenital heart disease circulation is 95%.5 By contrast, the 6-month survival of adults with normally structured hearts supported by extracorporeal BiVAD is poor at 56%.6 With continuous-flow LVAD for BiVAD, median 30-day survival is 90% and median 12-month survival is 58.5%.7 Shiose and colleagues2 developed EC-TCPC in patients with fulminant myocarditis with biventricular heart failure and demonstrated positive outcomes.
Potential RV bypass options are the Glenn procedure, classic Fontan procedure, and EC-TCPC. The Glenn and classic Fontan procedures are relatively simple compared with EC-TCPC. However, our simulation showed that the Glenn procedure resulted in uneven blood flow distribution and that the classic Fontan procedure resulted in substantial energy loss. With Fontan circulation, low right atrial pressure and even distribution of blood flow to the left and right PAs are extremely important for preventing secondary complications.8 Therefore, EC-TCPC was considered appropriate in our case.
For surgeons able to perform total artificial heart or BiVAD implantation, EC-TCPC might not be critical. We opted for this surgery to improve hemodynamics and to prevent high central venous pressure–associated complications, such as liver and kidney impairment or LVAD failure due to RV enlargement. Patients with fulminant myocarditis in cardiac arrest or those with advanced biventricular failure are considered candidates for EC-TCPC. Given the complexity of the procedure, it is preferable to initially opt for HeartMate3 plus RVAD and then carefully assess the procedure’s appropriateness.
A limitation of this hemodynamic analysis is that the model assumes asystole. Importantly, the results might differ according to the right-sided heart function and pulmonary conditions.
In conclusion, LVAD implantation with EC-TCPC can be a feasible option for patients with severe biventricular heart failure.
Acknowledgments
Funding Sources
The authors have no funding sources to disclose.
Disclosures
The authors have no conflicts of interest to disclose.
Patient Consent
Obtained.
References
- 1.Tadokoro N., Fukushima S., Minami K., et al. Efficacy of central extracorporeal life support for patients with fulminant myocarditis and cardiogenic shock. Eur J Cardiothorac Surg. 2021;60:1184–1192. doi: 10.1093/ejcts/ezab231. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Shiose A., Tanoue Y., Ushijima T., Tatewaki H. Simultaneous performance of implantable left ventricular assist device implantation and the Fontan operation in a patient with fulminant myocarditis leading to asystole. J Heart Lung Transplant. 2020;39:988–990. doi: 10.1016/j.healun.2020.04.013. [DOI] [PubMed] [Google Scholar]
- 3.Succi G.M., Moreira L.F., Leirner A.A., Silva R.S., Stolf N.A. Cavopulmonary anastomosis improves left ventricular assist device support in acute biventricular failure. Eur J Cardiothorac Surg. 2009;35:528–533. doi: 10.1016/j.ejcts.2008.11.026. [DOI] [PubMed] [Google Scholar]
- 4.Itatani K., Miyaji K., Nakahata Y., Ohara K., Takamoto S., Ishii M. The lower limit of the pulmonary artery index for the extracardiac Fontan circulation. J Thorac Cardiovasc Surg. 2011;142:127–135. doi: 10.1016/j.jtcvs.2010.11.033. [DOI] [PubMed] [Google Scholar]
- 5.Peng D.M., Koehl D.A., Cantor R.S., et al. Outcomes of children with congenital heart disease implanted with ventricular assist devices: an analysis of the Pediatric Interagency Registry for Mechanical Circulatory Support (PEDIMACS) J Heart Lung Transplant. 2019;38:420–430. doi: 10.1016/j.healun.2018.10.008. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Cleveland J.C., Jr., Naftel D.C., Reece T.B., et al. Survival after biventricular assist device implantation: an analysis of the Interagency Registry for Mechanically Assisted Circulatory Support database. J Heart Lung Transplant. 2011;30:862–869. doi: 10.1016/j.healun.2011.04.004. [DOI] [PubMed] [Google Scholar]
- 7.Farag J., Woldendorp K., McNamara N., et al. Contemporary outcomes of continuous-flow biventricular assist devices. Ann Cardiothorac Surg. 2021;10:311–328. doi: 10.21037/acs-2021-cfmcs-34. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Van De Bruaene A., Claessen G., Salaets T., et al. Late Fontan circulatory failure. What drives systemic venous congestion and low cardiac output in adult Fontan patients? Front Cardiovasc Med. 2022;9 doi: 10.3389/fcvm.2022.825472. [DOI] [PMC free article] [PubMed] [Google Scholar]