Postoperative Mean Pulmonary Artery Pressure Research Articles

Clinicopathological Correlation of Chronic Thromboembolic Pulmonary Hypertension: A Retrospective Study.

The pathophysiology of chronic thromboembolic pulmonary hypertension (CTEPH) is largely unknown. Although pulmonary endarterectomy (PEA) is potentially curative, inoperable patients and persistent pulmonary hypertension (PH) following surgery remain a significant problem. In this study, we aim to describe the histopathological characteristics of CTEPH and explore the potential relationship between pulmonary arterial lesions, radiological parameters, and clinical manifestations. Endarterectomized tissues from 81 consecutive patients of CTEPH were carefully collected, sectioned, and examined by experienced pathologists. Pertinent clinical and radiological data were obtained from medical records and operative reports. Neointima, fresh/organized thrombi, recanalized regions, and atherosclerotic lesions were microscopically examined as previously described. Thrombi and atherosclerosis were dominant in UCSD classification level I PEA materials, while recanalized neo-vessels were more frequently observed in UCSD classification level III cases. Degenerative changes of the extracellular matrix were also noticed in the vascular bed. Atherosclerotic lesions were more frequently observed in cases with higher ratio of the pulmonary artery diameter to ascending aorta diameter (PA/AA) reflected by computed tomographic pulmonary arterial scanning. Furthermore, the removal of pulmonary artery complex lesions (with the combination of three to four types of lesions) by PEA was associated with lower postoperative mean pulmonary arterial pressure (mPAP) and decreased incidences of persistent PH. Our study demonstrates that the histopathological features of CTEPH are strongly linked with clinical manifestations and the postoperative outcome after PEA. These data may provide possible evidence for further studies in searching for appropriate causal factors underlying this disease.

Association of residual pulmonary hypertension with survival after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension

This study investigated whether residual pulmonary hypertension (PH), defined as early postoperative mean pulmonary artery pressure (mPAP) of ≥30 mmHg, after undergoing pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) was associated with long‐term survival. All patients who underwent PEA for CTEPH at two Scandinavian centers were included in this study. Baseline characteristics and vital statuses were obtained from patient charts and national health‐data registers. The patients were then categorized based on residual PH measured via right heart catheterization within 48 h after undergoing PEA. Crude and weighted flexible parametric survival models were used to estimate the association between residual PH and all‐cause mortality and to quantify absolute survival differences. From 1992 to 2020, 444 patients underwent surgery. We excluded 6 patients who died on the day of surgery and 12 patients whose early postoperative pulmonary hemodynamic data was unavailable. Of the total study population (n = 426), 174 (41%) and 252 (59%) patients had an early postoperative mPAP <30 and ≥30 mmHg, respectively. After weighting, there was a significant association between residual PH and all‐cause mortality (hazard ratio: 2.49; 95% confidence interval [CI]: 1.60–3.87), and the absolute survival difference between the groups at 10 and 20 years was –22% (95% CI: –32% to –12%) and–32% (95% CI: –47% to –18%), respectively. A strong and clinically relevant association of residual PH with long‐term survival after PEA for CTEPH was found. After accounting for differences in baseline characteristics, the absolute survival difference at long‐term follow‐up was clinically meaningful and imply careful surveillance to improve clinical outcomes in these patients. Early postoperative right heart catheter measurements of mPAP seem to be helpful for prognostication following PEA for CTEPH.

Noninvasive follow-up strategy after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension.

BackgroundThe success of pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) is usually evaluated by performing a right heart catheterisation (RHC). Here, we investigate whether residual pulmonary hypertension (PH) can be sufficiently excluded without the need for a RHC, by making use of early post-operative haemodynamics, or N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiopulmonary exercise testing (CPET) and transthoracic echocardiography (TTE) 6 months after PEA.MethodsIn an observational analysis, residual PH after PEA measured by RHC was related to haemodynamic data from the post-operative intensive care unit time and data from a 6-month follow-up assessment including NT-proBNP, TTE and CPET. After dichotomisation and univariate analysis, sensitivity, specificity, positive predictive value, negative predictive value (NPV) and likelihood ratios were calculated.ResultsThirty-six out of 92 included patients had residual PH 6 months after PEA (39%). Correlation between early post-operative and 6-month follow-up mean pulmonary artery pressure was moderate (Spearman rho 0.465, p<0.001). Early haemodynamics did not predict late success. NT-proBNP >300 ng·L−1 had insufficient NPV (0.71) to exclude residual PH. Probability for PH on TTE had a moderate NPV (0.74) for residual PH. Peak oxygen consumption (V′O2) <80% predicted had the highest sensitivity (0.85) and NPV (0.84) for residual PH.ConclusionsCPET 6 months after PEA, and to a lesser extent TTE, can be used to exclude residual CTEPH, thereby safely reducing the number of patients needing to undergo re-RHC after PEA.

Characteristics and in-hospital outcomes of patients undergoing balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: a time-trend analysis from the Japanese nationwide registry

BackgroundBalloon pulmonary angioplasty (BPA), a novel technique initially introduced as a treatment for inoperable chronic thromboembolic pulmonary hypertension, is now increasingly being performed in a broader spectrum of patients. Here,...

Results of Fontan in Patients with Apicocaval Juxtaposition or/and Separated Hepatic Venous Drainage

Objective: Modifications of the Fontan operation, which are also known as total cavopulmonary connection (TCPC), are widely applied for patients with functionally univentricular hearts (FUH). Herein, we summed up the different surgical pathways and clinical outcomes in FUH patients with apicocaval juxtaposition (ACJ) or/and separated hepatic venous (SHV) drainage. Methods: Between January 2009 and December 2019, 123 patients who undergone TCPC in our institute were included in this retrospective study. We have included 70 patients with ACJ (Group 1) and 53 patients with SHV (Group 2). Moreover, Group 2 included 17 cases combing with ACJ (32.1%). In Group 1, three different TCPC methods were conducted. While 45 cases were conducted with the extracardiac conduit-TCPC(EC-TCPC) method, 24 cases used the intracardiac conduit-TCPC(IC-TCPC) method, and only one case used the lateral tunnel-TCPC(LT-TCPC). In Group 2, four TCPC methods were conducted on patients. Forty cases used the EC-TCPC-common open technique, 6 cases with IC-TCPC technique, 4 cases with LT-TCPC, and 3 cases with intra-extracardiac conduit-TCPC(IEC-TCPC). Results: There were 7 patients in Group 1 and 14 patients in Group 2 who required early re-operation during hospitalization (p < 0.05). Postoperative mean pulmonary artery pressure (mPAP) greater than 15 mmHg emerged as a predictor for early re-operation (p < 0.01) and early death (p < 0.001) in univariate analysis. Conclusions: TCPC can be performed in these patients and shows beneficial results. Under the Fontan principle of connecting systemic venous to the pulmonary vasculature unimpededly, surgeons should carefully evaluate three components when choosing for the surgical technique: The distance between inferior vena cava (IVC) and the apex; the site of the vertebrae relative to the ACJ; the distance between ACJ and SHV if coexisting. However, the technique should be altered when the postoperative mPAP was greater than 15 mmHg.

Survival and predictors of mortality in patients after the Fontan operation

As a result of the surgical techniques now being employed, the survival rate in patients after undergoing the Fontan operation has improved. The aims of this study were focused on determining the survival rate and predictors of early mortality. In a retrospective cohort study, 117 consecutive patients who underwent the Fontan operation were recruited. Multivariate Cox proportional regression analysis was used to assess the predictors of early mortality, defined as death within 30 days after the Fontan operation. The median follow-up time was 6.1 years. The median age at the time of the Fontan operation was 5.7 years. Survival rates in the patients at 5, 10, and 15 years postoperatively were 92%, 87% and 84%, respectively. Using univariate Cox regression analysis, the predictors of early mortality were found to be postoperative mean pulmonary artery pressure ≥23 mm Hg (hazard ratio 26.0), renal failure (hazard ratio 9.5), heterotaxy syndrome (hazard ratio 5.3), and uncorrected moderate or severe atrioventricular valve regurgitation (hazard ratio 9.4). After adjusting for confounding factors using multivariate Cox regression analysis, the predictors of early mortality were found to be postoperative mean pulmonary artery pressure ≥23 mm Hg (hazard ratio 23.2) and uncorrected moderate or severe atrioventricular valve regurgitation (hazard ratio 8.2). Uncorrected moderate or severe atrioventricular valve regurgitation and postoperative mean pulmonary artery pressure ≥23 mm Hg are independent predictors of early mortality after the Fontan operation. Patients with these factors should undergo aggressive management to minimize morbidity and mortality.

The expression of survivin in irreversible pulmonary arterial hypertension rats and its value in evaluating the reversibility of pulmonary arterial hypertension secondary to congenital heart disease.

The reversibility of pulmonary arterial hypertension (PAH) determines the operability of congenital heart disease (CHD) complicating with PAH, but it lacks a method for evaluating the reversibility. The current study aims to investigate the serum survivin level in irreversible PAH rats and to explore its potential as a biomarker for evaluating the reversibility of PAH in CHD patients. Irreversible PAH rats were characterized by prominent obstructive lesions resulting from the intimal formation, which was associated with decreased apoptosis and increased survivin expression, while reversible PAH rats were featured by medial hypertrophy resulting in mild occlusion, with increased apoptosis and unchanged survivin expression. In addition, the serum survivin was significantly increased in irreversible PAH rats when compared to both reversible PAH and control rats, and a positive correlation of serum survivin with survivin expression in the lung was confirmed. Third, the preoperative serum survivin was significantly higher in patients with irreversible CHD-PAH than in these with reversible CHD-PAH, and significant correlations between the serum survivin and BNP, preoperative pulmonary vascular resistance index, and postoperative mean pulmonary arterial pressure were also identified. In conclusion, the increased survivin level is a feature of irreversible PAH and the serum survivin represents a candidate biomarker reflecting the operability of CHD-PAH patients.

Extracorporeal membrane oxygenation after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension.

Pulmonary endarterectomy (PEA) is the treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH) but can result in respiratory and cardiac complications that may require extracorporeal membrane oxygenation (ECMO). We reviewed our experience with ECMO in patients undergoing PEA. Between January 2012 and August 2015, 35 patients underwent PEA for CTEPH. In all, four patients (11%) required veno-arterial (V-A) ECMO support due to severe cardiac and respiratory failure, including severe reperfusion pulmonary edema and persistent pulmonary hypertension. No significant differences in preoperative characteristics were found between patients who required ECMO and those who did not require ECMO. ECMO support was associated with a significantly higher incidence of postoperative respiratory complications, a longer intensive care unit stay, increased in-hospital mortality, residual pulmonary hypertension, and postoperative balloon pulmonary angioplasty (BPA). The postoperative mean pulmonary artery pressure and pulmonary vascular resistance were significantly higher in patients requiring ECMO. All patients requiring ECMO were successfully weaned off ECMO support (100%), and three of them were discharged from the hospital alive (75%). Patients with CTEPH may benefit from ECMO after PEA for cardiac and respiratory complications. A prompt decision to use V-A ECMO is critical for a successful outcome in these patients.

Reverse Remodeling of Pulmonary Arterioles After Pulmonary Artery Banding in Patients ≥ 2 Years Old with Severe Pulmonary ArterialHypertension and Congenital Heart Disease.

The purpose of this study was to evaluate the pathological changes of the pulmonary arterioles in patients ≥ 2 years of age who first underwent a pulmonary artery banding (PAB) procedure, followed by bidirectional Glenn or Fontan according to their specific conditions. This was a prospective study of 15 children diagnosed and treated with PAB at the Department of Cardiothoracic Surgery of Anzhen Hospital between January 2009 and December 2012. The percentage of media area (%MS) of pulmonary arteriole, the percentage of media thickness (%MT), and pulmonary arterial density (APSC) were calculated from lung tissue sections. Pulmonary artery pressure decreased significantly after PAB surgery (P < 0.01). Postoperative mean pulmonary artery pressure declined significantly (P < 0.01), the cardiothoracic ratio was reduced (P < 0.05), and percutaneous oxygen saturation (inhaled air) decreased to 80-85% (P < 0.01). %MT (from 35.1 ± 5.6% to 26.9 ± 4.3%, P < 0.01), %MS (from 51.4 ± 6.7% to 32.2 ± 7.4%, P < 0.01), and APSC (from 108.3 ± 38.5 to 83.6 ± 19.6, P < 0.01) were decreased significantly after PAB. Five patients underwent the bidirectional Glenn procedure and four underwent Fontan. In conclusion, the results suggest that PAB can reduce pulmonary artery pressure and that pulmonary arterial lesions can be reversed after PAB.

Comparison of Outcomes of Living-Donor Lobar and Cadaveric Lung Transplantation in Patients with Pulmonary Arterial Hypertension

Purpose Lung transplantation is indicated in patients with severe pulmonary arterial hypertension (PAH). Living donor lobar lung transplantation (LDLLT) may be considered in patients who might not survive the longer waiting duration for cadaveric lung transplantation (CLT). This study compared the outcomes of LDLLT and CLT in patients with PAH. Methods Retrospective review of medical records from our institutional database between April 2008 and August 2018 revealed 191 lung transplants, of which 6 LDLLTs and 10 CLTs were performed for PAH patients, defined based on the criteria for group 1 of the Nice classification. Results Preoperatively, LDLLT and CLT groups showed no significant differences in age (median 14 vs. 29.5 years, p=0.08), height (median 155 vs. 160 cm, p=0.91), mean pulmonary arterial pressure (PAP) (median 60.5 vs. 57.0 mmHg, p=0.96), brain natriuretic peptide (median 153 vs. 89.0 pg/mL, p=0.36), and dose of intravenous epoprostenol (median 29.7 vs. 65.2 ng/kg/min, p=0.55). All cases of LDLLT were bilateral, except one performed in a pediatric patient. In 2 cases, bilateral LDLLTs were performed by preserving the upper lobes for size mismatch. After surgery, extracorporeal cardiopulmonary support was required in 5 LDLLT cases and 4 CLT cases (p= 0.384). One hospital death occured on day 192 due to sepsis in the CLT group. The median postoperative PAP was 16.5 mmHg and 14.0 mmHg (p=0.213) and the ratio between the pre- and postoperative mean PAP were 26.6% and 26.4% (p=0.456) in the LDLLT and CLT groups, respectively. The median follow-up period was 57.5 and 22.5 months and the five-year survival was 100% and 88.9% (p=0.41) in LDLLT and CLT groups, respectively. Conclusion LDLLTs were associated with acceptable outcomes in patients with PAH and were not inferior to CLTs. Thus, for patients with severe progressive PAH, LDLLTs may be a lifesaving procedure. Lung transplantation is indicated in patients with severe pulmonary arterial hypertension (PAH). Living donor lobar lung transplantation (LDLLT) may be considered in patients who might not survive the longer waiting duration for cadaveric lung transplantation (CLT). This study compared the outcomes of LDLLT and CLT in patients with PAH. Retrospective review of medical records from our institutional database between April 2008 and August 2018 revealed 191 lung transplants, of which 6 LDLLTs and 10 CLTs were performed for PAH patients, defined based on the criteria for group 1 of the Nice classification. Preoperatively, LDLLT and CLT groups showed no significant differences in age (median 14 vs. 29.5 years, p=0.08), height (median 155 vs. 160 cm, p=0.91), mean pulmonary arterial pressure (PAP) (median 60.5 vs. 57.0 mmHg, p=0.96), brain natriuretic peptide (median 153 vs. 89.0 pg/mL, p=0.36), and dose of intravenous epoprostenol (median 29.7 vs. 65.2 ng/kg/min, p=0.55). All cases of LDLLT were bilateral, except one performed in a pediatric patient. In 2 cases, bilateral LDLLTs were performed by preserving the upper lobes for size mismatch. After surgery, extracorporeal cardiopulmonary support was required in 5 LDLLT cases and 4 CLT cases (p= 0.384). One hospital death occured on day 192 due to sepsis in the CLT group. The median postoperative PAP was 16.5 mmHg and 14.0 mmHg (p=0.213) and the ratio between the pre- and postoperative mean PAP were 26.6% and 26.4% (p=0.456) in the LDLLT and CLT groups, respectively. The median follow-up period was 57.5 and 22.5 months and the five-year survival was 100% and 88.9% (p=0.41) in LDLLT and CLT groups, respectively. LDLLTs were associated with acceptable outcomes in patients with PAH and were not inferior to CLTs. Thus, for patients with severe progressive PAH, LDLLTs may be a lifesaving procedure.

4:12 PM Abstract No. 229 The thromboaspiration with INDIGO system reduces the time and dose of fibrinolysis and improves the results in massive pulmonary embolism in comparison with catheter fragmentation (previous cohort study)

Determine if thromboaspiration with indigo system improves short- and medium-term outcomes compared with interventional treatment of choice for pulmonary embolism (PE) (mechanical thrombolysis + catheter-directed thrombolytic therapy). From Apr-2016 to Aug-2017, 43 patients diagnosed massive PE and a comparative with previous study of 111 patients with massive PE. In the first cohort all patients were treated with thromboaspiration + catheter-directed thrombolytic therapy (TAs) and the other cohort were treated with conventionally according to our protocol: thrombolysis + catheter fragmentation (MFT). There were no significant differences in age, sex and the angiographic pulmonary index (Miller index). Pulmonary pressures after fibrinolysis and one month later were compared. The total dose and the total time of fibrinolysis were also compared in both groups. Postoperative mean pulmonary arterial pressure (PAPm) was 34.06 ± 5.81 mm Hg TAs and 39.46 ± 6.39 mm Hg MFT, without showing significant differences in both groups regarding the 24hours and after 1- month angiographic control. There were significant differences in the total dose administered of urokinase (UK) (1.38 ± 0.25 IU of UK TAs MFT vs 2.82 ± 0.89 million IU of UK MFT) and the total time of UK perfusion (13.05 ± 1.70 hours TAs vs. 21.69 ± 11.92 hours MFT). four patients (9.3%) died in the follow-up in the cohort TAs with only 1 (2.3%) related to PE vs. 7 patients (6.3%) with only 4 (3.6%) related to PE or complications of endovascular treatment MFT. Thromboaspiration improves the results of conventional mechanical fragmentation and catheter-directed thrombolytic therapy, decreasing the time and total dosage of fibrinolysis and also decreasing PAP more rapidly.

Pathologic markers for evaluation of reversibility in pulmonary hypertension related to congenital heart disease

To assess the pathologic markers for evaluation of reversibility in pulmonary hypertension (PAH) related to congenital heart disease. Twenty-eight patients with congenital heart disease complicated by PAH were subclassified into reversible pulmonary hypertension (RPAH) and irreversible pulmonary hypertension (IPAH), according to post-operative mean pulmonary artery pressure (MPAP). Pulmonary vascular lesion was analyzed according to Ruan's method. Mean medium thickness percent, mean medium area percent and pulmonary arteriolar density were measured by quantitative morphometry. Immunohistochemical study for transgelin and filamin A was carried out. Amongst the 28 cases studied, 24 were RPAH and 4 were IPAH. Of the 24 patients with RPAH, 13 (54.2%, 13/24) had pulmonary vascular lesion of grade 0, 9 (37.5%, 9/24) of grade 1 and 2 (8.3%, 2/24) of grade 2. Of the 4 patients with IPAH, 1 had lesion of grade 1, 1 of grade 2 and 2 of grade 3. Both preoperative and postoperative MPAP were higher in IPAH patients than that in RPAH patients[(53.3±23.4) mmHg versus (34.1±12.7) mmHg, P=0.020 and (35.0±8.8) mmHg versus (17.8±3.9) mmHg, P<0.01]. Compared to patients with pulmonary vascular lesion of grades 0 and 1, the preoperative MPAP in patients with grades 2 and 3 showed no significant difference, but the postoperative MPAP was higher (P<0.05 or 0.01). Compared to control group, mean medium thickness percent and mean medium area percent were significantly higher in RPAH and IPAH categories (12.0±3.5, 8.5±2.0 versus 5.7±1.0, P<0.01 and 55.8±11.1, 49.0±9.4 versus 34.0±5.5, P<0.01). Mean medium thickness percent was significantly higher in IPAP group than that in RPAH group (12.0±3.5 versus 8.5±2.0, P=0.001). Correlation analysis demonstrated that mean medium thickness percent and mean medium area percent had positive correlation with preoperative and postoperative MPAP. There was no correlation between grading of pulmonary vascular lesion and reversibility. Transgelin and filamin A had stronger staining in pulmonary vascular smooth muscle cells in IPAH than those in RPAH and controls(P<0.05). Pathologic assessment of lung biopsy remains the gold standard for evaluation of the reversibility in PAH related to congenital heart disease. Mean medium thickness percent, mean medium area percent and immunoreactivity for transgelin and filamin A are useful parameters.

Pulmonary endarterectomy in severe chronic thromboembolic pulmonary hypertension

The outcome of patients with chronic thromboembolic pulmonary hypertension (CTEPH) undergoing pulmonary endarterectomy (PEA) after urgent hospitalization for decompensated right heart failure (DRHF) remains unclear. Among 120 consecutive patients undergoing PEA, 16 (13%) presented with a history of urgent hospitalization for DRHF (severe RHF group). This group was compared with the remaining 104 patients presenting with total peripheral vascular resistance (TPR) < 1,200 dynes · sec · cm(-5) (n = 78, control group) and >1,200 dynes · sec · cm(-5) (n = 26, high TPR group). DRHF occurred predominantly in patients with TPR > 1,200 dynes · sec · cm(-5) (prevalence of 32% vs 5% in patients with TPR < 1,200 dynes · sec · cm(-5), p < 0.0001). The overall in-hospital mortality after PEA was 4% (n = 5). All deaths occurred in patients with TPR > 1,200 dynes · sec · cm(-5) and DRHF. The proportion of patients with residual PH immediately after surgery was higher in the high TPR group (50%) and severe RHF group (56%) compared with the control group (29%; p = 0.04). In multivariate analysis, risk factors for residual PH after surgery were TPR > 1,200 dynes · sec · cm(-5), Jamieson disease Type III-IV, and female gender. A history of DRHF by itself was not a risk factor for residual PH after PEA. The overall 5-year survival was 87%. After a median follow-up of 20 months, the proportion of patients receiving medical therapy for residual PH was higher in patients with post-operative mean pulmonary artery pressure ≥35 mm Hg (61% vs 9%, p = 0.0007). DRHF occurs more frequently in patients with TPR > 1,200 dynes · sec · cm(-5), increasing the operative risk in these patients. The outcome of patients with high TPR in the absence of DRHF is excellent. However, patients with residual mean pulmonary artery pressure ≥35 mm Hg frequently receive pulmonary hypertension therapy after PEA.

Decreased time constant of the pulmonary circulation in chronic thromboembolic pulmonary hypertension

This study analyzed the relationship between pulmonary vascular resistance (PVR) and pulmonary arterial compliance (Ca) in patients with idiopathic pulmonary arterial hypertension (IPAH) and proximal chronic thromboembolic pulmonary hypertension (CTEPH). It has recently been shown that the time constant of the pulmonary circulation (RC time constant), or PVR × Ca, remains unaltered in various forms and severities of pulmonary hypertension, with the exception of left heart failure. We reasoned that increased wave reflection in proximal CTEPH would be another cause of the decreased RC time constant. We conducted a retrospective analysis of invasive pulmonary hemodynamic measurements in IPAH (n = 78), proximal CTEPH (n = 91) before (pre) and after (post) pulmonary endarterectomy (PEA), and distal CTEPH (n = 53). Proximal CTEPH was defined by a postoperative mean pulmonary artery pressure (PAP) of ≤25 mmHg. Outcome measures were the RC time constant, PVR, Ca, and relationship between systolic and mean PAPs. The RC time constant for pre-PEA CTEPH was 0.49 ± 0.11 s compared with post-PEA-CTEPH (0.37 ± 0.11 s, P < 0.0001), IPAH (0.63 ± 0.14 s, P < 0.001), and distal CTEPH (0.55 ± 0.12 s, P < 0.05). A shorter RC time constant was associated with a disproportionate decrease in systolic PAP with respect to mean PAP. We concluded that the pulmonary RC time constant is decreased in proximal CTEPH compared with IPAH, pre- and post-PEA, which may be explained by increased wave reflection but also, importantly, by persistent structural changes after the removal of proximal obstructions. A reduced RC time constant in CTEPH is in accord with a wider pulse pressure and hence greater right ventricular work for a given mean PAP.

Long-term outcome after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension

Pulmonary endarterectomy is the treatment of choice for chronic thromboembolic pulmonary hypertension. Although several reports demonstrated excellent medium-term survival after pulmonary endarterectomy, long-term outcomes remain unclear. We reviewed long-term outcomes and determined risk factors for early and late adverse events. Seventy-seven patients were studied. Mean pulmonary arterial pressure was 47±10 mm Hg and pulmonary vascular resistance was 868±319 dyne·s·cm(-5). Disease was classified as chronic thromboembolic pulmonary hypertension type 1 (n=61), type 2 (n=12), or type 3 (n=4). Median and maximum follow-up periods were 5.6 and 20 years, respectively. There were 11 in-hospital deaths. Nonsurvivors had significantly higher mean pulmonary arterial pressure and pulmonary vascular resistance than did survivors (54±10 vs 46±10 mm Hg; P=.02; 1124±303 vs 824±303 dyne·s·cm(-5); P<.01). In multivariate analysis, preoperative pulmonary vascular resistance was associated with in-hospital death (odds ratio, 1.003; 95% confidence interval, 1.001-1.005; P<.01). During follow-up, there were 10 all-cause deaths, including 5 related to chronic thromboembolic pulmonary hypertension. Freedom from adverse events, including disease-specific death or New York Heart Association functional class III, was 70% at 10 years. In the Cox proportional hazard model, postoperative mean pulmonary arterial pressure was associated with adverse events (hazard ratio, 1.12; 95% confidence interval, 1.03-1.21; P<.01). Receiver operating characteristic curve analysis showed mean pulmonary arterial pressure of 34 mm Hg as cutoff for adverse events. Pulmonary endarterectomy had sustained favorable effects on long-term survival. High pulmonary vascular resistance was associated with in-hospital death, and postoperative mean pulmonary arterial pressure was an independent predictor of adverse events.

Circulating big endothelin-1: An active role in pulmonary thromboendarterectomy?

Pulmonary thromboendarterectomy is an effective treatment for patients with chronic thromboembolic pulmonary hypertension. The early postoperative course may be associated with pulmonary vasoconstriction and profound systemic vasodilation. We investigated the potential involvement of endothelins in these hemodynamic alterations. Seventeen patients with chronic thromboembolic pulmonary hypertension (pulmonary vascular resistance, 1015 +/- 402 dyne x s x cm(-5) [mean +/- SD]) underwent pulmonary thromboendarterectomy with cardiopulmonary bypass and deep hypothermic circulatory arrest. Peripheral arterial blood samples were drawn before sternotomy, during cardiopulmonary bypass before and after deep hypothermic circulatory arrest, and 0, 8, 16, and 24 hours after surgery and were analyzed for big endothelin-1. The patients were divided into 2 groups according to whether their preoperative big endothelin-1 plasma level was above or below the cutoff point of 2.1 pg/mL, as determined by receiver operating characteristic curve analysis (group A, big endothelin-1 <2.1 pg/mL, n = 8; group B, big endothelin-1 > or =2.1 pg/mL, n = 9). Patients in group B, with higher preoperative big endothelin-1 levels (3.2 +/- 1.0 pg/mL vs 1.5 +/- 0.4 pg/mL; P < .001), were poorer operative candidates (preoperative mean pulmonary artery pressure, 51.3 +/- 7.1 mm Hg vs 43.6 +/- 6.2 mm Hg; P = .006) and had a poorer outcome (mean pulmonary artery pressure 24 hours after surgery, 32.6 +/- 9.5 mm Hg vs 21.8 +/- 6.2 mm Hg; P < .001). Positive correlations were found between preoperative big endothelin-1 levels and preoperative mean pulmonary artery pressure (r = 0.56; P = .02) as well as postoperative mean pulmonary artery pressure at 0 hours (r = 0.70; P = .002) and 24 hours (r = 0.63; P = .006) after surgery. Preoperative big endothelin-1 levels predicted outcome (postoperative mean pulmonary artery pressure at 24 hours after surgery) after pulmonary thromboendarterectomy (area under the receiver operating characteristic curve, 0.85). Peak big endothelin-1 levels also correlated with maximal vasopressor dosage (r = 0.65; P = .004). Preoperative big endothelin-1 levels seem to correlate with the hemodynamic alterations observed in pulmonary thromboendarterectomy and may be used to predict hemodynamic outcome after pulmonary thromboendarterectomy.

Chronic thromboembolic pulmonary arterial hypertension: correlation of postoperative results of thromboendarterectomy with preoperative helical contrast-enhanced computed tomography.

Pulmonary thromboendarterectomy is the treatment of choice for patients with chronic thromboembolic pulmonary arterial hypertension (CTEPH). Some patients do poorly after this procedure and may be better candidates for heart-lung transplant. The purpose of this study was to correlate preoperative findings on helical contrast-enhanced computed tomography (CT) with surgical outcome. Thirty-seven patients (mean age 52.9, range 22-71) who underwent pulmonary thromboendarterectomy and had preoperative helical contrast-enhanced CT followed by High Resolution CT (HRCT) scans were included in the study. The CTs were evaluated for the presence of central and segmental disease and for the presence of mosaic perfusion pattern. The presence of central disease, as well as the presence of segmental disease, correlated negatively with the postoperative mean pulmonary arterial pressure [r(c) = -0.401, P = 0.015, r(s) = -0.38, P = 0.024)] and the pulmonary vascular resistance [(r(c) = -0.37, P = 0.027, r(s) = -0.39, P = 0.019]. No correlation was found between the clinical variables and the presence of mosaic perfusion pattern. Patients with CTEPH and evidence of chronic PE in the central or segmental pulmonary arteries have a better clinical outcome after pulmonary thromboendarterectomy than patients without these findings. The presence of mosaic perfusion pattern is not helpful in predicting postoperative outcome.

Preoperative partitioning of pulmonary vascular resistance correlates with early outcome after thromboendarterectomy for chronic thromboembolic pulmonary hypertension.

Pulmonary thromboendarterectomy (PTE) is the preferred treatment for chronic thromboembolic pulmonary hypertension (CTEPH), but persistent pulmonary hypertension after PTE, as a result of either inaccessible distal thrombotic material or coexistent intrinsic small-vessel disease, remains a major determinant of poor outcome. Conventional preoperative evaluation is unreliable in identifying patients at risk for persistent pulmonary hypertension or predicting postoperative hemodynamic outcome. We postulated that pulmonary arterial occlusion pressure waveform analysis, a technique that has been used for partitioning pulmonary vascular resistance, might identify CTEPH patients with significant distal, small-vessel disease. Twenty-six patients underwent preoperative right heart catheterization before PTE. Pulmonary artery occlusion waveform recordings were performed in triplicate. Postoperative hemodynamics after PTE were compared with preoperative partitioning of pulmonary vascular resistance derived from the occlusion data. Preoperative assessment of upstream resistance (Rup) correlated with both postoperative total pulmonary resistance index (R2=0.79, P<0.001) and postoperative mean pulmonary artery pressure (R2=0.75, P<0.001). All 4 postoperative deaths occurred in patients with a preoperative Rup <60%. Pulmonary arterial occlusion pressure waveform analysis may identify CTEPH patients at risk for persistent pulmonary hypertension and poor outcome after PTE. Patients with CTEPH and Rup value <60% appear to be at highest risk.

The changes in main pulmonary artery pressure after bilateral lung autotransplantation in dogs.

In the Respiratory Center, Yongdong Severance Hospital, Yonsei University, we performed 10 cases of bilateral lung autotransplantation in mongrel dogs from July 1994 to June 1996, and we have analyzed the hemodynamic changes. Autotransplantation was performed in order to avoid postoperative rejection. The lung was flushed with an Euro-Collins(E-C) solution containing PGE1 which passed through a 10 French catheter inserted into an incision on the anterior half of the pulmonary artery to pulmonary parenchyme, and the vertical incision was made on the anterior half of the left atrium near the proximal part of the pulmonary vein. However, the bronchus was totally divided after clamping both sides. The lung was kept cold (4 degrees C) in the thoracic cavity for an hour by using slushed ice made from an E-C solution. After an hour of cold ischemia, the pulmonary artery was sutured with Prolene 5-0. The pulmonary vein was sutured with Prolene 6-0 by using the continuous everting mattress method. The main bronchus was anastomosed using the telescope method. The arterial oxygen concentration and the pressures in the femoral and pulmonary arteries were measured both preoperatively and postoperatively. There were no significant hemodynamic differences between the preoperative and postoperative mean pulmonary artery pressure (MPAP) (paired t-test, P = 0.05). Lung preservation using a cold (4 degrees C) E-C solution containing PGE1 may be an acceptable method for short-term storage of a lung (for about an hour) in bilateral lung autotransplantation in dogs.

Continuous low dose inhaled nitric oxide for treatment of severe pulmonary hypertension after cardiac surgery in paediatric patients.

To assess the effect of inhaled nitric oxide (NO) on severe postoperative pulmonary hypertension in children after surgical repair of a congenital heart defect. A pilot study of NO administration to 7 consecutive children who required adrenergic support and in whom postoperative mean pulmonary artery pressure was more than two thirds of mean systemic pressure and persisted despite alkalotic hyperventilation. Routine care after cardiac surgery for congenital heart disease in a multidisciplinary paediatric intensive care unit. Continuous inhalation of NO, initially at 15 ppm. Therefore, daily attempts at complete weaning or at reducing NO to the lowest effective dose. In 6 of the 7 children NO inhalation selectively decreased mean (SD) pulmonary artery pressure from 51 (12) to 31 (9) mm Hg (P < 0.05) while mean systemic arterial pressure was unchanged (68 (10) v 71 (7) mm Hg) (NS) and the arteriovenous difference in oxygen content decreased from 6.7 (0.9) to 4.8 (0.8) vol% (P < 0.05). Concomitantly PaO2 increased from 158 (98) to 231 (79) mm Hg) (P < 0.05). The seventh child showed no response to NO up to 80 ppm, could not be weaned from cardiopulmonary bypass, and died in the operating room. In responders, attempts at early weaning from NO inhalation always failed and NO at concentrations of less than 10 ppm was continuously administered for a median of 9.5 days (range 4 to 16 days) until complete weaning was possible from a mean dose of 3.9 (2.9) ppm. Methaemoglobinaemia remained below 2% and nitrogen dioxide concentrations usually ranged from 0.1 to 0.2 ppm. One child later died and five were discharged. A few months after surgery Doppler echocardiography (and catheterisation in one) showed evidence of regression of pulmonary hypertension in all 5. Inhalation of NO reduced pulmonary artery pressure in children with severe pulmonary hypertension after cardiac surgery and this effect was maintained over several days at concentrations carrying little risk of toxicity.