Secondary left heart failure occurred during VA-ECMO assistance for severe residual pulmonary hypertension after pulmonary endarterectomy: a case report

Background In patients of chronic thromboembolic pulmonary hypertension undergoing pulmonary endarterectomy, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides full haemodynamic support. However, during a rescue treatment of VA-ECMO for patients with difficulty weaning from cardiopulmonary bypass, a significantly increase left ventricular afterload through retrograde infusion of arterialized blood into the descending aorta may occur. Case presentation We report a 70-year-old man who suffered severe residual pulmonary hypertension following pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension. Preoperative echocardiogram showed a dilated and poorly functioning right ventricle, as well as a small left heart with normal function (TAPES9.6 mm, LVEF64%, average E/E′11.94, lateral E′12.1 cm/s, tricuspid regurgitation velocity 2.5 m/s), while postoperative echocardiography revealed a significant decrease of whole ventricular function on postoperative day 1(TAPES4mm, LVEF28%, average E/E′15, lateral E′6.7 cm/s, tricuspid regurgitation velocity 4.1 m/s), indicating the patient developed severe secondary left ventricular dysfunction on the basis of right ventricular dysfunction, during VA-ECMO support. Then comprehensive measures were adopted, such as down-regulating VA-ECMO flow rate, adjusting respiratory parameters, using vasoactive drugs, as well as prostacyclin. Eventually, the pulmonary hypertension decreased to moderate degree, and the heart function improved gradually. Conclusions In the face of severe residual pulmonary hypertension and sencondary left ventricular dysfunction associated with VA-ECMO, comprehensive measures described above may facilitate recovery. ECMO flow titration to maintain relatively low flow rate is very important to not only maintain systemic perfusion, but also reduce left ventricular afterload and ensure pulsatile perfusion of pulmonary artery.

Simple and Short-term Inspiration Training Accelerates Recovery from Residual Pulmonary Hypertension after Mitral Valve Surgery: A randomized control trial

Background: Residual pulmonary hypertension after mitral valve surgery predicts a worse prognosis. This study aimed to explore the effect of inspiratory muscle training on functional capacity and pulmonary artery pressure in patients with residual pulmonary hypertension after mitral valve surgery. Methods: Forty-three patients with residual pulmonary hypertension soon after mitral valve repair or replacement surgery were consecutively enrolled in this randomised controlled trial. They were randomly allocated to either an intervention group (n=22) or a control group (n=21). Both groups participated in usual 10-12 sessions of supervised aerobic exercise training, with low to moderate intensity. The subjects in the intervention group participated in additional inspiratory muscle training using an incentive spirometer with a series of 10-12 inspiration repetitions of 50% of maximum inspiratory volume in each aerobic session. Echocardiography and the 6-minute walking test were performed before and after the programme. Results: The patients were 70% female, mean age 43.5+/-13 years. Both groups had similar baseline characteristics. The systolic pulmonary artery pressure declined from 51(43-68) mmHg to 35 (29-39) mmHg, p<0.001 in intervention group, and from 46(43-55) mmHg to 43(40-51)mmHg, p<0.01 in control group. The reduction was higher in the intervention group than in the control group, 16 (12-30) vs 3.5 (2-4) mmHg respectively, p<0.001, and in patients with higher baseline systolic pulmonary artery pressure. The 6-minute walk test distance increased from 308(242-353) meters to 407(377-433) meter, p<0.01 in intervention group, and from 353(334-381) meter to 391(376-429) meter, p<0.01 in control group. The improvement was higher in the intervention group than in control group, 101 (93-131) vs 48 (35-53) meter respectively, p<0.001. Conclusion: Adding inspiratory muscle training to a usual exercise programme resulted in faster recovery from residual pulmonary hypertension and higher increase in functional capacity.

Computed tomography angiographic parameters of pulmonary artery as prognostic factors of residual pulmonary hypertension after pulmonary endarterectomy

Objectives This study aimed to retrospectively assess using computed tomography pulmonary angiography (CTPA) for predicting residual pulmonary hypertension (RPH) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) after pulmonary endarterectomy (PEA). Methods We retrospectively analyzed data of 131 patients with CTEPH who underwent PEA in our center (2008–2015). We measured several diameters of the pulmonary artery and thoracic aorta preoperatively. We evaluated the relationship between these measurements (and their indices) and signs of RPH represented by pulmonary artery systolic pressure (PASP) estimated by echocardiography. Results Significant correlations were observed between the aortopulmonary index and prediction of any residual hypertension and moderate/severe hypertension 1 year after PEA, and any residual hypertension and severe hypertension 2 years after PEA. The aortopulmonary index was significantly related to a reduction in PASP 1 year after the operation. A lower aortopulmonary index (≤0.88 for the ascending aorta and ≤0.64 for the descending aorta) predicted lower RPH. Conclusions Preoperative CTPA parameters can be used to assess the risk of RPH after PEA. The aortopulmonary index has significant predictive value for RPH and a reduction in PASP after PEA. Lower values of the aortopulmonary index suggest a better outcome after PEA.

Cardiopulmonary exercise test could predict residual pulmonary hypertension after pulmonary endarterectomy

Introduction Pathophysiology of chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by thrombotic lesions at pulmonary arteries and arteriolar remodeling in distal regions. There is an increase in pulmonary vascular resistance that will lead to heart failure and early death without treatment. Currently, pulmonary endarterectomy (PE) is the potentially curative treatment for this condition. Cardiopulmonary exercise test (CPET) allows to quantify functional improvement after PE. Objective: To analyze changes in CPET and hemodynamic parameters after surgery in a cohort of patients with CTEPH. Methods 502 patients with CTEPH have been evaluated until December 2018, PE was performed in 255 (51%). In 49 patients, CPET was available before and 6 months after surgery. Residual pulmonary hypertension (RPH) was defined as mean pulmonary arterial pressure ≥30 mmHg evaluated by right cardiac catheterization at 3–6 months after PE. Results 54% were men, mean age 48±13 years. Two thirds of patients were in functional class II/III at time of diagnosis and with severe hemodynamic and functional profile. Hemodynamics and CPET parameters improved after surgery. However, in patients with RPH they did not improve significantly. Results are shown in table. Conclusions PE restores functional capacity in CTEPH, represented by significant improvement in CPET parameters. CPET is emerging as a non-invasive technique suitable of detecting RPH. More studies are needed to confirm this hypothesis. Funding Acknowledgement Type of funding source: None

Beneficial effects of balloon pulmonary angioplasty on clinical outcomes in patients with residual pulmonary hypertension after pulmonary endarterectomy

Background Although pulmonary endarterectomy (PEA) is an established surgical treatment for chronic thromboembolic pulmonary hypertension (CTEPH), a part of patients after PEA show residual pulmonary hypertension, leading to limited exercise capacity. Recently, several studies have indicated that balloon pulmonary angioplasty (BPA) improves hemodynamics, exercise capacity and prognosis in inoperable CTEPH patients. However, the effects of BPA in patients with residual pulmonary hypertension after PEA remain to be elucidated. Aim In the present study, we investigated comprehensive efficacy of BPA on hemodynamics, exercise capacity and right ventricular function in those with residual pulmonary hypertension after PEA. Methods From October 2010 to February 2019, 227 patients with CTEPH underwent PEA in our institution. Right heart catheterization after PEA (median follow up period from PEA to right heart catheterization 39 [10.5, 90] months) showed that 55 patients showed residual PH (mean pulmonary artery pressure (mPAP)≥25mmHg), and 38 of them referred to BPA (mean age 57 years old, male 8 (21%)) due to residual symptoms. In 29 out of 38 patients (76%) who completed BPA and underwent follow-up right heart catheterization, we examined hemodynamics, exercise capacity and right ventricular function before and after BPA. Follow-up examination was performed 3 months after last BPA session. Results In this study population (N=29), PEA significantly improved mPAP (47±7 to 38±10 mmHg), pulmonary vascular resistance (PVR, 14.6±4.6 to 9.2±4.6 WU) and right ventricular ejection fraction measured by magnetic resonance imaging (26.6±11.3 to 38.4±6.8%) (Figure). Median period from PEA to first BPA procedure was 42 [13.5, 94] months. Total session number during study period was 160 sessions, and mean session number of BPA was 5.5±1.5 per patient. Follow-up study revealed that BPA additionally improved mPAP (38±10 to 27±8 mmHg) and PVR (9.2±4.6 to 5.1±2.2 WU) (Figure). Similarly, 6-minute walk distance (393±125 to 452±125 m) and peak VO2 (16.4±3.8 to 18.1±4.6 ml/min/kg, p&lt;0.05) were increased, and WHO functional class also significantly improved by BPA (I/II/III/IV, 0/21/8/ 0 to 1/27/1/0, p&lt;0.01). In addition, right ventricular ejection fraction (38.4±6.8 to 44.2±7.1%) was increased after BPA (Figure). There were no procedure-related deaths and major lung injuries requiring oral intubation during study period. 3-year survival in patients after BPA was 100% (median follow-up period after last BPA session, 32 [18, 46] months). Conclusion In CTEPH patients with residual pulmonary hypertension after PEA, additional BPA significantly improved hemodynamics, right ventricular function, exercise capacity and residual symptoms without severe complications, leading to good prognosis. These results suggest that combination therapy of PEA and BPA could be an effective therapeutic option for post PEA patients with residual symptoms and exercise limitation. Figure 1 Funding Acknowledgement Type of funding source: None

The extent of enlarged bronchial arteries is not correlated with the development of reperfusion pulmonary edema after pulmonary endarterectomy in patients with chronic thromboembolic pulmonary hypertension

This study investigated whether dilated bronchial arteries are associated with reperfusion pulmonary edema in patients with chronic thromboembolic pulmonary hypertension. Results showed that the extent of enlarged bronchial arteries was not associated with the development of reperfusion pulmonary edema, whereas the residual pulmonary hypertension had a significant association.

Dynamic vascular changes in chronic thromboembolic pulmonary hypertension after pulmonary endarterectomy

Residual pulmonary hypertension is an important sequela after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension. Recurrent thrombosis or embolism could be a contributor to this residual pulmonary hypertension but the potential extent of its role is unknown in part because data on incidence are lacking. We aimed to analyze the incidence of new intravascular abnormalities after pulmonary endarterectomy and determine hemodynamic and functional implications. A total of 33 chronic thromboembolic pulmonary hypertension patients underwent routine CT pulmonary angiography before and six months after pulmonary endarterectomy, together with right heart catheterization and exercise testing. New vascular lesions were defined as (1) a normal pulmonary artery before pulmonary endarterectomy and containing a thrombus, web, or early tapering six months after pulmonary endarterectomy or (2) a pulmonary artery already containing thrombus, web, or early tapering at baseline, but increasing six months after pulmonary endarterectomy. Nine of 33 (27%) chronic thromboembolic pulmonary hypertension patients showed new vascular lesions on CT pulmonary angiography six months after pulmonary endarterectomy. In a subgroup of patients undergoing CT pulmonary angiography 18 months after pulmonary endarterectomy, no further changes in lesions were noted. Hemodynamic and functional outcomes were not different between patients with and without new vascular lesions. New vascular lesions are common after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension; currently their origin, dynamics, and long-term consequences remain unknown.