Low Pulmonary Artery Wedge Pressure Research Articles

Underfilling decreases left ventricular function in pulmonary arterial hypertension

To evaluate the association between impaired left ventricular (LV) longitudinal function and LV underfilling in patients with pulmonary arterial hypertension (PAH). Thirty-nine patients with PAH and 18 age and sex-matched healthy controls were included. LV volume and left atrial volume (LAV) were delineated in short-axis cardiac magnetic resonance (CMR) cine images. LV longitudinal function was assessed from atrio-ventricular plane displacement (AVPD) and global longitudinal strain (GLS) was assessed using feature tracking in three long-axis views. LV filling was assessed by LAV and by pulmonary artery wedge pressure (PAWP) using right heart catheterisation. Patients had a smaller LAV, LV volume and stroke volume as well as a lower LV-AVPD and LV-GLS than controls. PAWP was 6 [IQR 5––9] mmHg in patients. LV ejection fraction did not differ between groups. LV stroke volume correlated with LV-AVPD (r = 0.445, p = .001), LV-GLS (r = − 0.549, p < 0.0001) and LAVmax (r = .585, p < 0.0001). Furthermore, LV-AVPD (r = .598) and LV-GLS (r = − 0.675) correlated with LAVmax (p < 0.0001 for both). Neither LV-AVPD, LV-GLS, LAVmax nor stroke volume correlated with PAWP. Impaired LV longitudinal function was associated with low stroke volume, low PAWP and a small LAV in PAH. Small stroke volumes and LAV, together with normal LA pressure, implies that the mechanism causing reduced LV longitudinal function is underfilling rather than an intrinsic LV dysfunction in PAH.

Usefulness of the Pulmonary Arterial Systolic Pressure to Predict Pulmonary Arterial Wedge Pressure in Patients With Normal Left Ventricular Systolic Function

Tissue Doppler imaging combined with transmitral Doppler permits estimation of pulmonary artery wedge pressure (PAWP) in many, but not all, patients, whereas pulmonary artery systolic pressure (PASP) and cardiac output (time-velocity integral method) are routinely measured. It was hypothesized that simple Doppler echocardiographic measurements could be used to estimate PAWP in many patients by rearranging the equation for pulmonary vascular resistance ([mean pulmonary artery pressure - (left atrial pressure/cardiac output)] x 80). Data from 69 patients (mean age 59 +/- 15 years) were reviewed, including cardiac output, transmitral mitral E wave velocity, and lateral tissue Doppler imaging mitral annular early diastolic velocity. PAWP was determined in the 2 ways of (1) measured (PAWPm) using the regression equation PAWPm = 1.91 + (1.24 * transmitral mitral E wave velocity/mitral annular early diastolic velocity) developed and validated by Nagueh, and (2) using a nomogram that we developed to predict PAWP when cardiac output and PASP were known. Moderately strong correlation was found between PASP and PAWPm (r = 0.73), and this correlation improved when excluding patients with pulmonary or liver disease and restricting cardiac output to 3.5 to 6.0 L/min (physiologic range; r = 0.81). Furthermore, the relation between PAWPm and PASP allowed for discrimination of high versus low PAWP: 36 of 37 patients with PASP < or =30 mm Hg had PAWPm < or =15 mm Hg (sensitivity 97%, specificity 47%). Conversely, 9 of 9 patients with PASP > or =40 mm Hg had PAWPm > or =12 mm Hg (sensitivity 100%, specificity 70%). Predicted PAWP correlated well with PAWPm (r = 0.63) and improved when patients with liver or pulmonary disease were excluded (r = 0.83). In conclusion, PASP strongly correlated with PAWP, and this principle can be exploited to rapidly detect patients with low or high PAWP.

Hypoalbuminemia in elderly patients with acute diastolic heart failure

ObjectivesThis study evaluated the relative contribution of serum colloid osmotic pressure (COP) lowering and pulmonary artery wedge pressure (PAWP) elevation in the pathogenesis of pulmonary edema in patients with systolic or isolated diastolic heart failure (DHF). BackgroundThe role of hypoalbuminemia and the resulting low COP have been shown in some patients with acute systolic heart failure (SHF). MethodsColloid osmotic pressure and PAWP were determined in 100 patients with acute heart failure (HF) (56 with DHF and 44 with SHF; mean age, 78 ± 12 years), in 35 patients with acute dyspnea from pulmonary origin, and in 15 normal controls. Pulmonary artery wedge pressure was estimated using transthoracic Doppler echocardiography. ResultsColloid osmotic pressure was significantly lower in the DHF group (20.5 ± 5 mm Hg) than in the SHF group (24.2 ± 3.7 mm Hg, p < 0.001), pulmonary disease group (25.1 ± 4.2 mm Hg, p < 0.001), or normal control group (24.7 ± 3 mm Hg). Low COP resulted from hypoalbuminemia due to age, malnutrition, and sepsis. Pulmonary artery wedge pressure was significantly higher in patients with SHF (26 ± 6.3 mm Hg) than in the patients with DHF (20.3 ± 7 mm Hg, p < 0.001) and was significantly higher in the patients with DHF than in the patients with pulmonary disease (13 ± 4.2 mm Hg, p < 0.001). The COP–PAWP gradient was similar in patients with SHF (−1.6 ± 7.1 mm Hg) and patients with DHF (0.7 ± 6 mm Hg). ConclusionsFrequent hypoalbuminemia resulting in low COP facilitates the onset of pulmonary edema in patients with DHF who usually have lower PAWP than patients with SHF.

ADDITIONAL DOSE OF APROTININ MAY IMPROVE HEMODYNAMICS DURING POSTREPERFUSION PERIOD IN PATIENTS UNDERGOING ORTHOTOPIC LIVER TRANSPLANTATION (OLT)

S123 The role of possible antiinflammatory effects of Aprotinin (APR) in different clinical situations has been reported [1]. The positive influence of APR on hemodynamics during OLT was recognized as well [2]. The reperfusion of the transplanted liver graft by unclamping inferior vena cava and portal vein causes depression of cardiovascular system. The most common findings are: hypotension, bradyrrhythmia, low systemic vascular resistance, increased venous filling pressure, decreased cardiac output and myocardial depression. This could be related to vasoactive substances or myocardial depressant factors released from the grafted liver [3]. We assessed the effects of additional dose of APR given before reperfusion on hemodynamics during postreperfusion period. METHODS: Eighteen patients, aged 36-66, who underwent OLT without veno-venous bypass (VVB) were given APR in high dose: 2,000,000 kallikrein inactivation units (KIU) at the beginning of surgery followed by continuous infusion of 500,000 KIU/h until the end of surgery. Patients were divided into two groups: nine patients received 500,000 KIU of APR 5 min before reperfusion. The second group of 9 patients did not. The following hemodynamic data were recorded 5 min before and 5 min after reperfusion: mean arterial pressure (MAP), central venous pressure (CVP), mean arterial pulmonary pressure (PAP-M), pulmonary artery wedge pressure (PAWP), systemic vascular resistance (SVR), and cardiac index (CI). Statistical analysis was done using Student's t-test, and p < 0.05 was considered as significant. RESULTS: No significant differences were found regarding age, weight, Child's classification of liver failure, and hemodynamics before reperfusion. Significantly higher SVR, MAP, a lower PAP-M, CVP, and trend toward lower PAWP and CI were noted in APR group. (Table 1)Table 1CONCLUSIONS: These results suggest that additional dose of APR before reperfusion may improve hemodynamics during postreperfusion period. These findings could be explained by possible antiinflammatory effects of APR. Higher dose of APR may be needed to achieve these effects.

END-DIASTOLIC VOLUME VERSUS PULMONARY ARTERY WEDGE PRESSURE IN EVALUATING CARDIAC PRELOAD IN TRAUMA PATIENTS

To evaluate the relative accuracy of right ventricular end-diastolic volume index (RVEDVI) and pulmonary artery wedge pressure (PAWP) for determining cardiac preload. A modified pulmonary artery catheter was used to determine RVEDVI, PAWP, and CI 238 times in 32 trauma patients. The initial mean values included cardiac index (CI) = 3.4 +/- 1.3 L/min/m2, PAWP = 14.8 +/- 6.6 mm Hg, and RVEDVI = 99 +/- 40 mL/m2. Cardiac index correlated better with RVEDVI (r = 0.6440; p < 0.001) than with PAWP (r = 0.1068) or CVP (r = 0.1604). In 84 studies in 19 patients, the PAWP was high (19+ mm Hg) in spite of an RVEDVI that was low (< 90 mL/m2) in 22 (26%) or mid-range (90-140 mL/m2) in 49 (58%) of these. In addition, in 12 studies a high RVEDVI (> 140 mL/m2) existed with a relatively low PAWP (< 12 mm Hg). Thus, in 83 (35%) of the studies, PAWP provided information different from the RVEDVI. Of 65 instances in which preload was increased, CI "responded" (> or = 20%) in 26 (40%). The incidence of a response was not affected by the PAWP; however, responses with a RVEDVI of < 90, 90-140, or > 140 mL/m2 were 64%, 27%, and 0 (p < 0.001). The RVEDVI more accurately predicted preload recruitable increases in CI than did the PAWP.

Partial anomalous pulmonary venous drainage associated with mitral stenosis with an intact atrial septum: A distinctive hemodynamic syndrome

A case of partial anomalous venous drainage associated with mitral stenosis and intact interatrial septum is presented. The hemodynamic findings consisted of pulmonary hypertension, markedly elevated pulmonary artery wedge pressure and large left-to-right shunt at the atrial level. These findings are distinctive of an intact septum, because in Lutembacher's syndrome there is a tendency for equalization of pressure in the atria and, therefore, the pulmonary artery wedge pressure may be normal or only slightly elevated. The findings of high and low pulmonary artery wedge pressure in different parts of lungs may be additional evidence for presence of partial anomalous venous connection.