The impact of bronchiolitis obliterans on late morbidity and mortality after single and bilateral lung transplantation for pulmonary hypertension

Surgical Treatment of Pulmonary Arterial Hypertension

Significant advances in the treatment of pulmonary arterial hypertension have occurred in the last several years. The decision to refer a patient for transplantation requires a dynamic approach. Candidate selection and timing of referral to transplant centers is critical for success, particularly with current allocation protocols that do not take into account the severity of illness. Though long-term success is tempered by chronic allograft dysfunction and infection, considerable improvements in outcomes have established lung transplantation for pulmonary arterial hypertension as an efficacious and life-prolonging treatment. However, transplantation should be reserved for patients who have failed the best available medical therapy. Ideally, transplantation occurs when the clinically deteriorating patient has enough reserve to survive long enough to be transplanted but is not debilitated enough to jeopardize the graft. There is significant uncertainty with regard to this ideal.

Impact of pulmonary hypertension on the outcomes of noncardiac surgery: predictors of perioperative morbidity and mortality

OBJECTIVES

We sought to determine the predictors of short-term morbidity and mortality (< 30 days) after noncardiac surgery in patients with pulmonary hypertension (PH).

BACKGROUND

Pulmonary hypertension is considered to be a significant preoperative risk factor.

METHODS

The PH and surgical data bases were matched from 1991 to 2003. Patients were excluded if PH was secondary to left heart disease, not present before surgery, or the procedure involved cardiopulmonary bypass. Univariate and multivariate logistic regression analyses were used to identify variables associated with short-term morbidity and mortality.

RESULTS

Of 1,276 patients in the PH database, 145 patients (73% female) met all study criteria. The mean age (+/-SD) was 60.1 +/- 16.0 years. Right ventricular systolic pressure (RVSP) (mean +/- SD) on the two-dimensional echocardiogram was 68 +/- 21 mm Hg. There were 60 patients (42%) who experienced one or more short-term morbid event(s) (1.8 events/patient experiencing any event). A history of pulmonary embolism (p = 0.01), New York Heart Association functional class > or = II (p = 0.02), intermediate- to high-risk surgery (p = 0.04), and duration of anesthesia > 3 h (p = 0.04) were independent predictors of short-term morbidity. There were 10 early deaths (7%). A history of pulmonary embolism (p = 0.04), right-axis deviation (p = 0.02), right ventricular (RV) hypertrophy (p = 0.04), RV index of myocardial performance > or = 0.75 (p = 0.03), RVSP/systolic blood pressure > or = 0.66 (p = 0.01), intraoperative use of vasopressors (p < 0.01), and anesthesia when nitrous oxide was not used (p < 0.01) were each associated with postoperative mortality.

CONCLUSIONS

In patients with PH undergoing noncardiac surgery with general anesthesia, specific clinical, diagnostic, and intraoperative factors may predict worse outcomes.

Anti-monocyte chemoattractant protein-1 gene therapy attenuates pulmonary hypertension in rats

Monocyte/macrophage chemoattractant protein-1 (MCP-1), a potent chemoattractant chemokine and an activator for mononuclear cells, may play a role in the initiation and/or progression of pulmonary hypertension (PH). To determine whether blockade of a systemic MCP-1 signal pathway in vivo may prevent PH, we intramuscularly transduced a naked plasmid encoding a 7-NH(2) terminus-deleted dominant negative inhibitor of the MCP-1 (7ND MCP-1) gene in monocrotaline-induced PH. We also simultaneously gave a duplicate transfection at 2-wk intervals or skeletal muscle-directed in vivo electroporation (EP) to evaluate whether a longer or higher expression might be more effective. The intramuscular reporter gene expression was enhanced 10 times over that by EP than by simple injection, and a significant 7ND MCP-1 protein in plasma was detected only in the EP group. 7ND MCP-1 gene transfer significantly inhibited the progression of MCT-induced PH as evaluated by right ventricular systolic pressure, right ventricular hypertrophy, medial hypertrophy of pulmonary arterioles, and mononuclear cell infiltration into the lung. Differential effects of longer or higher transgene expression were not apparent. Although the in vivo kinetics of 7ND MCP-1 gene therapy should be studied further, these encouraging results suggest that an anti-inflammatory strategy via blockade of the MCP-1 signal pathway may be an alternative approach to treat subjects with PH.

Ten years experience with lung and heart-lung transplantation in primary and secondary pulmonary hypertension

OBJECTIVE

Patients with primary pulmonary hypertension (PPHT) have a worse natural outcome compared with those with secondary pulmonary hypertension in Eisenmenger's syndrome (ES) and chronic pulmonary embolism (CPE). Lung transplantation (SLTx, DLTx, HLTx) still remains the only therapeutical option for patients with this type of endstage lung disease.

METHODS

From 1988 to 1998, 63 patients underwent lung transplantation for PPHT (n=29, 9 m, 20 f, 2 SLTx, 14 DLTx, 13 HLTx), ES (n=29, 13 m, 16 f, 2 SLTx, 3 DLTx, 24 HLTx) or CPE (n=5, 2 m, 3 f, 1 SLTx, 2 DLTx, 2 HLTx). Groups were comparable for NYHA functional class, preoperative pulmonary arterial pressure, recipient and donor age, ischemic time, necessity and duration of cardiopulmonary bypass and cross-match.

RESULTS

The 1-, 3- and 5-year survival was 52, 40 and 35% for the PPHT-group, 83, 78 and 74% for the ES-group and 80, 60 and 60% for the CPE-group, respectively (P=0.026, P=0.033, P=0.082 for 1-, 3- and 5-year survival). Patients following DLTx showed a lower 1-year survival rate as compared with patients after HLTx both in PPHT patients (36 vs. 62%, P=0.091) and in ES patients (67 vs. 83%, P=0.213). The incidence of bronchiolitis obliterans syndrome was 29% at 1 year and 45% at 3 years for the PPHT-group vs. 17 and 65% for the ES-group (n. s. in between groups). Excluding postoperative ventilation time (PPHT-group: 26.8+/-24.0 days vs. ES-group: 16.1+/-30.8 days, P=0. 011) and a higher incidence of infectious causes of death (PPHT-group n=8 vs. ES-group n=1, P=0.017) groups were comparable with regard to their postoperative courses.

CONCLUSIONS

It is concluded, that predominantly the underlying primary disease influences graft survival after lung transplantation in patients with pulmonary hypertension compared with all other patient and procedure dependent factors. Lung transplantation in patients with PPHT requires further investigations to achieve results comparable with other indications.