Characteristics and prognostic significance of right heart remodeling and tricuspid regurgitation after pulmonary endarterectomy

OBJECTIVE

Right heart remodeling and tricuspid regurgitation (TR) are common in patients with chronic thromboembolic pulmonary hypertension. This study aimed to investigate the significance of right heart remodeling and TR after pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension.

METHODS

Patients who underwent PEA with preoperative and postoperative transthoracic echocardiograms at our center between June 2010 and July 2019 were retrospectively reviewed. The composite end point was defined as death or hospitalization due to worsening heart failure, bleeding, or recurrent pulmonary embolism.

RESULTS

In total, 158 patients were included for analysis. Right ventricular basal (48 [45-52] vs 43 [39-47] mm, P < .001), midcavitary (46 [42-50] vs 38 [34-42] mm, P < .001), and longitudinal dimensions (87 [83-93] vs 80 [75-84] mm, P < .001), along with the right atrial volume index (37 [25-51] vs 24 [18-34] mL/m2, P < .001), significantly decreased, whereas left ventricular and atrial sizes and left ventricular ejection fraction increased after PEA. Overall, 78 patients (49%) showed significant TR on preoperative transthoracic echocardiograms, and 33 (21%) had significant residual TR after PEA. Fourteen patients died, and 24 patients met the composite end point. Residual TR after PEA was independently associated with mortality (P = .005) and the composite end point (P = .003). Patients with residual TR had significantly worse survival (log-rank P < .001) and greater event rates (log-rank P = .003) than those without residual TR.

CONCLUSIONS

Significant improvements in right heart remodeling were seen following PEA. However, residual TR was a poor prognostic marker.

Added value of 3D echocardiography in the diagnosis and prognostication of patients with right ventricular dysfunction

Recent inroads into percutaneous-based options for the treatment of tricuspid valve disease has brought to light how little we know about the behavior of the right ventricle in both health and disease and how incomplete our assessment of right ventricular (RV) physiology and function is using current non-invasive technology, in particular echocardiography. The purpose of this review is to provide an overview of what three-dimensional echocardiography (3DE) can offer currently to enhance RV evaluation and what the future may hold if we continue to improve the 3D evaluation of the right heart.

Impaired left and right systolic ventricular capacity in corrected atrial septal defect patients

Resting right ventricular (RV) systolic function has in some studies been shown to be impaired after correction of an atrial septal defect (ASD) whereas impairment of left ventricular (LV) systolic function is uncertain. In the present study we examine the LV and RV systolic response to exercise in patients with a previously corrected ASD in order to investigate the myocardial capacity. Thirty-six adult ASD patients with a corrected isolated secundum ASD and eighteen adult age-matched controls underent a semi-supine exercise stress echocardiographic examination. At rest, LV parameters were comparable between groups, and RV global longitudinal strain (RV-GLS) was lower for the ASD group (-18.5%, 95% CI -20.0--17.0%) compared with controls (-24.5%, 95% CI -27.7--22.4%, p < 0.001). At peak exercise, LV ejection fraction (LVEF) was lower for ASD patients (61%, 95% CI 58-65%) compared with controls (68%, 95% CI 64-73% p = 0.01). Peak LV global longitudinal strain (LV-GLS) was borderline significantly lower (ASD: -18.4%, 95% CI -20.2--16.6%, controls: -21.3%, 95% CI -23.6--19.0%, p = 0.059). Both RVEF (ASD: 64%, 95% CI 60-68%, controls: 73%, 95% CI 65-80%, p = 0.05) and tricuspid annular plane systolic excursion (TAPSE) (ASD: 2.5 cm, 95% CI 2.3-2.7 cm, controls: 3.2 cm, 95% CI 2.9-3.6 cm, p < 0.001) at peak exercise were lower for ASD patients. Exercise assessed peak oxygen uptake was comparable between groups (ASD: 32.8 mL O2/kg/min, 95% CI 30.3-35.5 mL O2/kg/min, controls: 35.2 mL O2/kg/min, 95% CI 31.6-38.8 mL O2/kg/min, p = 0.3). Corrected ASD patients demonstrate a reduced LV and RV systolic exercise response decades after ASD correction whereas resting parameters of LV and RV systolic function were within normal range. The presence of subclinical systolic myocardial dysfunction during exercise might be associated with the long-term morbidities documented in this patient group.

Pulmonary endarterectomy

Chronic thromboembolic pulmonary hypertension is an underdiagnosed condition. Patients typically present with the symptoms of right heart failure. Diagnosis is usually done by radionuclide ventilation/perfusion (VQ) scan, high-quality multidetector computed tomography (CT) or pulmonary angiography at expert centers. Pulmonary endarterectomy remains the corner stone in management of chronic thromboembolic pulmonary hypertension. Deep hypothermic circulatory arrest is commonly used for the operation at most centers. In-hospital mortality ranges from 1.7 to 14.2%. Pulmonary hemorrhage, reperfusion lung injury, and right ventricular failure remain major early post-operative concerns. Five-year survival is reported to be 76 to 89%. Long-term outcome depends on residual pulmonary hypertension. Balloon pulmonary angioplasty and medical management play an adjunctive role. Here, we provide a comprehensive review on surgical management of chronic thromboembolic pulmonary hypertension.

Reverse remodeling of tricuspid valve morphology and function in chronic thromboembolic pulmonary hypertension patients following pulmonary thromboendarterectomy: a cardiac magnetic resonance imaging and invasive hemodynamic study

BACKGROUND

To investigate changes in tricuspid annulus (TA) and tricuspid valve (TV) morphology among chronic thromboembolic pulmonary hypertension (CTEPH) patients before and 12 months after pulmonary thromboendarterectomy (PEA) and compare these findings to normal control subjects.

METHODS

20 CTEPH patients and 20 controls were enrolled in the study. The patients were examined with echocardiography, right heart catherization and cardiac magnetic resonance imaging prior to PEA and 12 months after.

RESULTS

Right atrium (RA) volume was significantly reduced from baseline to 12 months after PEA (30 ± 9 vs 23 ± 5 ml/m², p < 0.005). TA annular area in systole remained unchanged (p = 0.11) and was comparable to controls. The leaflet area, tenting volume and tenting height in systole were significantly increased at baseline but decreased significantly with comparable values to controls after 12 months (p < 0.005). There was correlation between the changes of right ventricular-pulmonary artery coupling and changes of TV tenting height (r = - 0.54, p = 0.02), TV tenting volume (r = - 0.73, p < 0.001) and TV leaflet area (- 0.57, p = 0.01) from baseline to 12 months after PEA. Tricuspid regurgitation jet area/RA area was significantly (p < 0.01) reduced from baseline (30 ± 13%) to 12 months after PEA (9 ± 10%).

CONCLUSION

In CTEPH patients selected for PEA, TV tenting height, volume and valve area are significantly increased whereas annulus size and shape are less affected. The alterations in TV morphology are fully reversed after PEA and correlates to improvements of right ventricular-pulmonary arterial coupling.

Is it time for a paradigm shift: Should double-lung transplant be considered the treatment of choice for idiopathic pulmonary arterial hypertension and giant pulmonary aneurysm?

Idiopathic pulmonary arterial hypertension is a rare condition, frequently complicated by pulmonary arteries' aneurysm. Aggressive medical therapy is often unsatisfactory and lung transplantation remains the only option. We report a unique case of severe idiopathic pulmonary arterial hypertension complicated by a giant pulmonary aneurism, massive pulmonary valve regurgitation, and right ventricle dysfunction. The patient was, as our first choice, listed for heart-lung transplantation and remained in emergency list for more than 7 months. Unfortunately, due to further clinical deterioration and the unavailability of a heart-lung bloc, plan B was mandatory. The patient underwent a combined procedure including: double lung transplant, pulmonary artery plasty, and sutureless pulmonary valve prosthesis with open deployment (first-in-man use in such scenario). Postoperative outcome was uneventful. Our thought is that double lung transplantation and conventional combined pulmonary artery/valve surgery should be considered as the first option avoiding excessive waiting times and potential further clinical deterioration.

Long-term changes of exercise hemodynamics and physical capacity in chronic thromboembolic pulmonary hypertension after pulmonary thromboendarterectomy

BACKGROUND

A substantial number of chronic thromboembolic pulmonary hypertension (CTEPH) patients experience dyspnea on exertion and limited exercise capacity despite surgically successful pulmonary endarterectomy (PEA). We sought to prospectively evaluate resting and peak exercise hemodynamics before, 3 and 12 months after PEA in consecutive CTEPH-patients and correlate it to physical functional capacity.

METHODS AND RESULTS

Twenty consecutive CTEPH-patients were examined. Twelve months after PEA, 75% of patients with severely increased pre-PEA mean pulmonary arterial pressure (mPAP) at rest had normal or mildly increased mPAP. However, mPAP reduction was less pronounced during exercise where only 45% had normal or mildly increased mPAP at 12 months. Hemodynamic changes during exercise were tested using the pressure-flow relationship (i.e. mPAP/cardiac output (CO) slope). The average mPAP/CO slope was 7.5 ± 4.2 mm Hg/L/min preoperatively and 3.9 ± 3.0 mm Hg/L/min at 12 months (p < .005). CO reserve (CO increase from rest to peak exercise) was increased (5.7 ± 2.9 L/min) 12 months after PEA compared with pre-PEA (2.5 ± 1.8 L/min), p < .0001. However, 12 months after PEA, the CO reserve was only 49% of that of healthy controls, p < .0001. Changes in cardiac output (∆CO), calculated as the difference between CO before PEA and 12 months later, were significantly correlated with six-minute-walk-test and peak oxygen uptake (VO2), both at rest and peak exercise.

CONCLUSION

Invasive exercise hemodynamic examination in CTEPH-patients demonstrates that after otherwise successful PEA surgery, >50% of patients have a significant increase in exercise mPAP, and the CO reserve remains compromised 12 months after PEA. Improvement in physical capacity is correlated with ∆CO.