Elevated Transpulmonary Gradient Research Articles

Pulmonary Vascular Dysfunction Is Associated with Poor Outcomes in Patients with Acute Lung Injury

Despite the recognition that acute lung injury (ALI) can elevate pulmonary artery (PA) pressure and right ventricular afterload, the impact of pulmonary vascular dysfunction on outcomes of these patients is not well defined. To investigate the impact of pulmonary vascular dysfunction in patients with acute lung injury. Secondary analysis of the Fluid and Catheter Treatment Trial. A total of 501 patients who received a PA catheter were evaluated for associations between increases in transpulmonary gradient (TPG) (PA mean pressure - PA occlusion pressure) or pulmonary vascular resistance index (PVRi) and 60-day mortality, ventilator-, intensive care unit (ICU)-, and cardiovascular-free days (days with mean arterial pressure ≥ 60 mm Hg off vasopressor support). We were able to measure the TPG in 475 (95%) and the PVRi in 470 (92%) patients. Patients with an elevated baseline TPG had an increased 60-day mortality (30 versus 19%; P = 0.02), and lower numbers of median ventilator- [25-75% quartiles] (15 [0-22] versus 19 [7-24]; P = 0.005), ICU- (14 [0-21] versus 18 [5-22]; P = 0.005), and cardiovascular-free days (23 [12-27] versus 25 [18-27]; P = 0.03). The median PVRi (305 [204-431] dyne s/cm⁵/m²) was elevated early in the course of ALI. PVRi was statistically higher in patients who died (326 [209-518] versus 299 [199-416]; P = 0.01). In individual multivariate models, TPG and PVRi remained independent risk factors for 60-day mortality and decrease in the number of ventilator-, ICU-, and cardiovascular-free days. Pulmonary vascular dysfunction is common in ALI, and is independently associated with poor outcomes. Future trials targeting pulmonary vascular dysfunction may be indicated.

Chronic sildenafil lowers transpulmonary gradient and improves cardiac output allowing successful heart transplantation

For patients undergoing heart transplantation, an elevated pulmonary vascular resistance (PVR) increases mortality in the early post-heart transplant period. This study aimed to assess the effects of chronic sildenafil administration on the PVR, transpulmonary gradient (TPG), and cardiac output (CO) in patients with heart failure awaiting heart transplantation. The data from serial right heart catheterizations (RHC) of six patients were analyzed. All patients demonstrated a reaction to the vasodilators glyceryl trinitrate or inhaled iloprost at initial RHC before commencing sildenafil. A follow-up RHC was performed as required to guide management. The average total daily dose of sildenafil was 100 mg for a period of 68+/-58 days (4-145). The average TPG at baseline was 23.7 mmHg and fell in 4 of the 6 patients (67%) with an average reduction of 4.5+/-7.3 mmHg (-5 to 14). The average PVR at baseline was 571 dyn s cm(-5) and fell in 5 of 6 patients (83%), with an average reduction of 167+/-266 dyn s cm(-5) (74-518). The CO at baseline was 3.95 L/min and rose in 5 of 6 patients (83%) with an average improvement of 0.58 L/min (-1.1 to 1.3). The mean pulmonary capillary wedge pressure (MPCWP) at baseline was 26.3 mmHg and fell in 5 of 6 patients (83%) with an average fall of 5.5 mmHg (-1 to 17). Four of the six patients achieved a final TPG<15 mmHg, which we consider to be acceptable for orthotopic heart transplantation, average 11 mmHg (8 to 13). Three of these patients have already undergone successful, uncomplicated heart transplantation. Chronic sildenafil use is safe and effective in reducing an elevated TPG and PVR in patients with heart failure requiring heart transplantation and allows patients to be transplanted who may otherwise have been excluded because of pulmonary hypertension.

Fontan Completion in Infants

Since the implementation of the Fontan procedure, several clinical factors have been linked to outcome. A study of the outcome after Fontan completion was undertaken with particular attention to the influence of age and cardiac diagnosis. Review of all patients (n = 107) undergoing Fontan completion between January 1998 and July 2005 to identify predictors of outcome: early death, prolonged effusions, and prolonged hospital stay. Median age was 13 months (range, 11 to 35) and median weight was 9.4 kgs (6.7 to 15.1). Hypoplastic left heart syndrome was present in 61 patients, and stage I Norwood was the initial palliation in 69. An interim superior cavopulmonary connection was performed in all. A lateral tunnel was used, and a deliberate right to left shunt was created in 99 patients. Mean transpulmonary gradient and pulmonary artery pressure were 5.7 +/- 1.5 mm Hg and 11.6 +/- 2.2 mm Hg, respectively. Median time to extubation was 5 hours (range, 2.5 to 184). Median duration of pleural effusion was 3 days (1 to 58) and was greater or equal to 14 days in 13 patients (12%). Overall mortality was 4.5% (5 of 107). Variables associated with poor outcome included associated noncardiac diagnosis (p < 0.05), elevated transpulmonary gradient (p = 0.03), and pulmonary artery pressure (p < 0.02). Hypoplastic left heart syndrome was the only variable associated with prolonged effusive complications. Fontan completion can be performed with good results in the first year of life independent of anatomic diagnosis. Significant noncardiac pathology, and a higher pulmonary artery pressure were predictive of worse outcome. Hypoplastic left heart syndrome was associated with prolonged effusions.

80: Does a positive vasodilator response to sildenafil predict survival after heart transplantation in patients with pulmonary hypertension?

Pulmonary hypertension (PH) with elevated transpulmonary gradient (TPG) is considered a major risk factor for increased early mortality after heart transplant (HT). Vasodilators are used to assess reversibility of PH, and a positive response seems to predict a better outcome. Sildenafil citrate is a selective inhibitor of phosphodiesterase type 5, which produces selective pulmonary vasodilation.

Sublingual sildenafil and reversibility of pulmonary hypertension in candidates to heart transplant

Pulmonary hypertension (PH) with elevated transpulmonary gradient (TPG) is a major risk factor for increased early mortality after heart transplant (HT). Vasodilators are used to assess reversibility of PH after a period of tailored therapy for heart failure. Sildenafil citrate is a selective inhibitor of phosphodiesterase type 5, responsible of cGMP degradation, producing pulmonary vasodilatation.

Prolonged continuous outpatient parenteral inotropic support in heart transplant candidates with reversible pulmonary hypertension

Background: Pulmonary hypertension (PH) in advanced congestive heart failure (CHF) is associated with increased mortality after heart transplantation. Reversibility of elevated transpulmonary gradient (TPG) by pharmacologic agents predicts improved early post-transplant outcome.