Related Experiment Videos
Hemodynamic evaluation of heterotopic heart transplantation
M Rigaud1, J P Bourdarias, E el Khoury
1Department of Cardiology, Hôpital Ambroise Paré, Boulogne, France.
Insights
In heterotopic heart transplants, the donor heart
Area of Science:
- Cardiology
- Transplantation Immunology
- Cardiovascular Surgery
Background:
- Heterotopic heart transplantation is a surgical procedure where a donor heart is placed alongside the recipient's native heart.
- Understanding the functional contribution of both native and donor hearts is crucial for optimizing patient outcomes.
- Previous studies have not fully elucidated the dynamic interplay between native and donor cardiac function post-transplant.
Purpose of the Study:
- To evaluate the relative contributions of native and donor hearts to overall circulatory function after heterotopic heart transplantation.
- To differentiate the functional roles of the donor heart based on native left ventricular performance.
Main Methods:
- Cardiac catheterization was performed on 10 patients who underwent heterotopic heart transplantation.
- Hemodynamic parameters including filling pressures, cardiac index, and pulmonary arteriolar resistance were measured.
- Patients were stratified into two groups based on aortic pressure waveform analysis.
Main Results:
- Significant improvements in circulatory function were observed, including decreased filling pressures, increased cardiac index, and reduced pulmonary arteriolar resistance.
- In Group I (severe native dysfunction), the donor heart assumed total or near-total ventricular workload, acting as a biventricular assist device.
- In Group II (less severe native dysfunction), the donor heart contributed partially to systemic and pulmonary blood flow, functioning as a partial biventricular assist device.
- Native left ventricular function deteriorated postoperatively in all patients, primarily due to reduced preload and increased afterload.
Conclusions:
- The donor heart's functional role in heterotopic transplantation is dependent on the preoperative status of the native heart.
- In patients with severe native left ventricular dysfunction, the donor heart compensates fully, mimicking a biventricular assist device.
- In patients with less severe native dysfunction, the donor heart acts as a partial assist device, augmenting native function.
Abstract:
To assess the relative contribution of native and donor hearts to total circulatory performance after heterotopic transplantation, we used cardiac catheterization to examine 10 patients. Left and right ventricular filling pressures significantly decreased by 41% and 36%, respectively, cardiac index increased by 25%, and pulmonary arteriolar resistance was reduced by 61%. Patients were subdivided into two groups according to the presence of one (group I) or two (group II) peaks on the aortic pressure curve. In group I, the donor left ventricle assumed total left ventricular work and 80% of right ventricular work. Because the native left ventricle could not generate enough pressure to open the aortic valve, its entire stroke volume was ejected into the common left atrium. In addition, in all four patients a native aortic regurgitation occurred in diastole and systole. In contrast, in group II, native left ventricular systolic pressure always exceeded aortic diastolic pressure. The donor left ventricle contributed 68% to systemic blood flow and the donor right ventricle 51% to pulmonary blood flow. Mild native aortic regurgitation was demonstrated in two patients only. Native left ventricular function deteriorated postoperatively in all patients (ejection fraction decreased from 0.22 +/- 0.09 to 0.14 +/- 0.08), but this deterioration was more marked in group I. Postoperative depression of native left ventricular function could not be ascribed to progression of coronary artery disease but was mainly due to reduced preload (competitive filling) and increased afterload. Thus in group I patients with more severe preoperative left ventricular dysfunction, the donor heart behaved like a total biventricular assist device. In contrast, in group II patients the donor heart acted like a partial biventricular assist device.