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Andrew D Michaels

Publications and source records attributed to Andrew D Michaels.

At least 19 recordsLinked to original sources
PubMed2007

Determination of adequate coronary stent expansion using StentBoost, a novel fluoroscopic image processing technique.

OBJECTIVE: We tested the hypothesis that the use of motion-corrected fluoroscopic images results in enhanced coronary stent visualization and improved detection of inadequate stent expansion. BACKGROUND: Intravascular ultrasound (IVUS) more accurately detects inadequate stent expansion when compared with coronary angiography. Stent under-expansion is associated with stent restenosis and thrombosis. Developing a technique to improve fluoroscopic-based assessment of stent expansion is desirable. METHODS: We analyzed measurements of 48 coronary stents implanted in 30 patients using quantitative coronary angiography (QCA), IVUS, and StentBoost (SB), a novel fluoroscopic image processing technique. Correlations of stent diameter between the modalities were determined. Using established IVUS criteria for adequate stent deployment, we assessed the diagnostic test characteristics of SB to detect inadequate stent expansion. RESULTS: Correlations of minimum stent diameter were highest between IVUS and SB (r=0.75; P<0.0001) when compared with QCA and IVUS (r=0.65; P<0.0001), and QCA and SB (r=0.49; P=0.0004). IVUS and SB demonstrated a small difference in minimum stent diameter, 0.043 mm (95% CI: 0.146-0.061 mm). The correlation between IVUS and SB was lower for vessels with intimal calcification (r=0.57; P=0.002) when compared with vessels with deeper calcification (r=0.84; P<0.0001). A SB minimum diameter of <2.5 mm predicted inadequate stent expansion by IVUS with 88% sensitivity, 70% specificity, and a positive likelihood ratio of 2.9. CONCLUSIONS: SB had superior correlations for stent expansion measured by IVUS when compared with QCA. A minimum stent diameter by SB measurement<2.5 mm is associated with inadequate stent expansion using IVUS criteria.

Aged↗
PubMed2006

Effectiveness of repeat enhanced external counterpulsation for refractory angina in patients failing to complete an initial course of therapy.

AIMS: This study examined the causes and results of retreatment of patients who failed to complete an initial 35-hour Enhanced External Counterpulsation (EECP) course. METHODS AND RESULTS: Data of 2,311 successive angina patients from the International EECP Patient Registry were analyzed, 86.5% completed their EECP course (Complete cohort). Of the 13.5% patients failing to complete the initial course (Incomplete cohort), 28.3% had repeat EECP within 1 year vs. 10.1% of the Complete group. The predictors of failure to complete the initial course of EECP were: female gender, heart failure, use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and use of nitroglycerin. For the Complete group, 83.4% had a reduction of at least one Canadian Cardiovascular Society (CCS) class after their initial EECP course, vs. 21.7% in the Incomplete group (p < 0.001). After repeat treatment, 66.2% of the Incomplete group achieved at least one CCS class reduction vs. 69.4% of the Complete group (p = NS) undergoing retreatment. The independent predictors for those who return to successfully complete their second course were patients who stopped their first course because of clinical events, and candidacy for coronary artery bypass grafting at the time of initial treatment. CONCLUSION: The results of retreatment of those who failed to complete their initial EECP course were comparable to those who completed their initial treatment, with similar reductions of CCS angina class.

Aged↗
PubMed2006

Effect of external counterpulsation on plasma nitric oxide and endothelin-1 levels.

Enhanced external counterpulsation (EECP) significantly augments diastolic blood flow and has been postulated to improve endothelial function by increased shear stress. We examined the effects of EECP on plasma nitric oxide and endothelin-1 (ET-1) levels. Plasma nitrate and nitrite (NOx) and ET-1 levels were measured serially in 13 patients with coronary artery disease who received 1-hour daily treatments of EECP over 6 weeks. During the course of EECP therapy, plasma NOx progressively increased and plasma ET-1 progressively decreased. After 36 hours of EECP, there was a 62 +/- 17% increase in plasma NOx compared with baseline (43.6 +/- 4.3 vs 27.1 +/- 2.6 micromol/L, p <0.0001) and a 36 +/- 8% decrease in plasma ET-1 (76.7 +/- 9.5 vs 119.5 +/- 8.5 pg/L, p <0.0001). At 3 months after completion of EECP, NOx remained 12 +/- 11% above baseline (p = 0.002), and ET-1 remained 11 +/- 10% below baseline (p = 0.0068). Our data provides neurohormonal evidence to support the hypothesis that EECP improves endothelial function.

Adult↗
PubMed2006

Relationship between accurate auscultation of a clinically useful third heart sound and level of experience.

BACKGROUND: Poor performance by physicians-in-training and interobserver variability between physicians have diminished clinicians' confidence in the value of the third heart sound (S3). METHODS: To determine whether auscultation of a clinically useful S3 improves with advancing levels of experience, we performed a prospective, blinded, observational study of 100 patients undergoing left-sided heart catheterization. Patients underwent blinded auscultation by 4 physicians (each from 1 of 4 different levels of experience), phonocardiography, measurement of blood B-type natriuretic peptide levels, echocardiography for measurement of left ventricular ejection fraction, and cardiac catheterization for measurement of left ventricular end-diastolic pressure. RESULTS: Whereas residents' and interns' auscultatory findings demonstrated no significant agreement with phonocardiographic findings, an S3 auscultated by cardiology fellows (kappa = 0.37; P<.001) and cardiology attendings (kappa = 0.29; P = .003) agreed with phonocardiographic findings. Although the sensitivities of the S3 were low (13%-52%) for identifying patients with abnormal measures of left ventricular function, the specificities were high (85%-95%), with the best test characteristics exhibited by phonocardiography and more experienced physicians. The S3 detected by attendings and fellows was superior in distinguishing an elevated B-type natriuretic peptide level, a depressed left ventricular ejection fraction, or an elevated left ventricular end-diastolic pressure (P = .002-.02 for attendings and .02-.03 for fellows) compared with residents (P = .02-.47) or interns (P = .09-.64). CONCLUSIONS: The S3 auscultated by more experienced physicians demonstrated fair agreement with phonocardiographic findings. Although correlations were superior for phonocardiography, the associations between the S3 and abnormal markers of left ventricular function improved with each level of auscultator experience.

Adult↗
PubMed2006

Phonocardiographic timing of third and fourth heart sounds during acute myocardial infarction.

A 47-year-old diabetic woman was referred for diagnostic coronary angiography as part of an evaluation before renal transplantation. During attempts to cannulate the left coronary artery, the patient developed severe dyspnea and new ST-segment elevations in the anterior leads. Left coronary angiography showed acute occlusion of the proximal left anterior descending (LAD) coronary artery. She then underwent emergent percutaneous intervention of the occluded vessel. Continuous electrocardiographic and phonocardiographic recordings were obtained during the procedure that documented the timing and appearance of ST-segment elevations and the onset of third and fourth heart sounds. In this report, the sequence of these events is discussed, and the literature is reviewed.

Coronary Disease↗
PubMed2006

Two-year outcomes in patients with mild refractory angina treated with enhanced external counterpulsation.

BACKGROUND: In the International Enhanced External Counterpulsation Patient Registry (IEPR), approximately 85% of the patients treated are in Canadian Cardiovascular Society (CCS) class III-IV with no option for further invasive coronary revascularization procedures. HYPOTHESIS: This study sought to determine whether it is clinically important to establish whether the observed durable reduction in disabling severe angina with enhanced external counterpulsation (EECP) treatment can be extended to those with less severe CCS class II angina, who also have no option for further revascularization. METHODS: This study evaluated the immediate response, durability and clinical events over a 2-year period after EECP treatment in 112 patients with Canadian Cardiovascular Society (CCS) class II angina versus 1346 patients with class III-IV angina using data from the International EECP Patient Registry (IEPR). RESULTS: Treatment with EECP significantly (by at least one CCS class) reduced angina frequency, nitroglycerin use, and improved quality of life in both groups. At 2-year follow-up, 74% of class II and 70% of class III-IV patients remained free of major adverse cardiovascular events (MACE) and continued to demonstrate a durable CCS class improvement over baseline. CONCLUSION: The robust effectiveness of EECP as a noninvasive device, together with its relatively low start-up and recurrent costs, makes it an attractive consideration for treating patients with milder refractory angina in addition to the patient with severely disabling angina treated in current practice.

Aged↗
PubMed2006

Impact of body mass index on outcomes of enhanced external counterpulsation therapy.

OBJECTIVES: We evaluated the association of baseline body mass index (BMI) on the outcomes of enhanced external counterpulsation (EECP) therapy for chronic stable angina. BACKGROUND: We are in the midst of a pandemic of obesity, which is complicating the care of patients with coronary artery disease (CAD). METHODS: We examined 2730 patients enrolled from 2002 to 2004 in the IEPR-2. Baseline and outcome variables were stratified by the entry BMI in kilograms per meter squared. RESULTS: Obesity (BMI > 30 kg/m2) was common (40.6%) among patients with severe CAD referred for EECP. Within the total cohort, 2.6% was underweight (BMI < or = 20 kg/m2) and 4.5% was morbidly obese (BMI > 40 kg/m2). Prevalence of diabetes, hypertension, dyslipidemia, and heart failure (HF) was higher in obese patients. However, the rates of baseline angina and prior revascularization were similar among the groups. The peak diastolic augmentation ratio was similar between groups during the first (0.7 +/- 0.4 for lowest and highest BMI) and last hours of treatment (0.9 +/- 0.5 and 0.8 +/- 0.5). The cumulative hours of treatment, the change in angina class, and the Duke Activity Status Index were similar for all BMI groups. There was a greater reduction in weekly anginal episodes from baseline across ascending levels of BMI (-6.3 +/- 13.6 to -9.7 +/- 15.8, P = .03). The rates of discontinuation for clinical events were highest (14.3%) with skin breakdown being the most frequent cause (10.1%) in the underweight. The rates of clinical events including myocardial infarction, HF, and death trended higher across ascending levels of BMI (P = .52). Multivariate analysis found that older age, history of stroke, history of HF, and diabetes, but not BMI, were predictors of clinical events. CONCLUSIONS: More than 40% of patients with severe CAD referred for EECP were obese. Underweight patients had higher rates of discontinuation of treatment mainly because of skin breakdown. Symptomatic benefit of EECP was similar among all BMI groups. However, despite symptomatic improvement, there was a nonsignificant trend for higher rates of myocardial infarction, HF, and death as BMI increased.

Aged↗
PubMed2006

High-sensitivity C-reactive protein and parameters of left ventricular dysfunction.

BACKGROUND: Elevated levels of high-sensitivity C-reactive protein (CRP), an inflammatory marker, have been associated with heart failure. However, it is not known which parameters of left ventricular dysfunction correlate with elevated levels of CRP. METHODS AND RESULTS: In this cross-sectional study of 98 patients referred for cardiac catheterization, we investigated whether commonly used clinical indices of left ventricular dysfunction correlated with CRP levels. CRP levels were elevated to a greater degree in participants with diabetes mellitus (P =.006) and heart failure (P =.003). Increased CRP levels were associated with increased plasma levels of B-type natriuretic peptide (BNP; P =.0001), decreased left ventricular ejection fraction (LVEF; P =.02), and increased left-ventricular end-diastolic pressure (LVEDP; P =.0005). After multivariable adjustment, LVEDP and CRP were independently associated (P =.046). CONCLUSION: CRP is increased in patients with heart failure. Of the clinical parameters of left ventricular dysfunction, direct measurement of left ventricular end-diastolic pressure is most closely associated with CRP.

Aged↗
PubMed2006

Nesiritide acutely increases pulmonary and systemic levels of nitric oxide in patients with pulmonary hypertension.

BACKGROUND: Pulmonary hypertension (PH) is characterized by decreased pulmonary vascular expression of nitric oxide (NOx), a vasodilator that increases levels of smooth muscle cyclic guanosine monophosphate (cGMP). This study investigated mechanisms by which the vasodilator B-type natriuretic peptide (BNP) affects the systemic and pulmonary vasculature in PH patients. METHODS AND RESULTS: Twenty PH patients with mean pulmonary artery (PA) pressure > 25 mm Hg were enrolled. Ten had precapillary (pulmonary capillary wedge pressure [PCWP] < or = 15 mm Hg) and 10 had postcapillary (PCWP > 15 mm Hg) PH. Right heart catheterization was performed before and 30 minutes after intravenous nesiritide infusion. NOx and cGMP levels from the PA and systemic (AO) arteries were obtained before and after nesiritide infusion. The postcapillary PH patients demonstrated significantly reduced pulmonary vascular resistance after nesiritide; there was no change in the precapillary PH cohort. NOx levels increased significantly in both AO (P < .0001) and PA (P = .0093), as did cGMP levels (P < .0001). There was a higher increase in NOx levels from the pulmonary arteries in precapillary PH patients compared to postcapillary PH patients (P = .020). CONCLUSION: In PH patients, nesiritide infusion significantly increases NOx levels, suggesting a novel mechanism for its vasodilatory effects. These responses may differ between pre- and postcapillary PH patients.

Adult↗
PubMed2006

Primer: practical approach to the selection of patients for and application of EECP.

Over the past decade, the frequency of use of enhanced external counterpulsation (EECP) has increased in patients with angina, irrespective of medical therapy and coronary revascularization status. Many patients referred for EECP have one or more comorbidities that could affect this treatment's efficacy, safety, or both. By use of data from more than 8,000 patients enrolled in the International EECP Patient Registry, we provide practical guidelines for the selection and treatment of patients. We have focused on considerations for patients who have one or more of the following characteristics: age older than 75 years, diabetes, obesity, heart failure, and peripheral vascular disease. We have also reviewed outcomes and treatment recommendations for individuals with poor diastolic augmentation during treatment, for those with atrial fibrillation or pacemakers, and for those receiving anticoagulation therapy. Lastly, we examined relevant data regarding extended courses of EECP, repeat therapy, or both. While clinical studies have demonstrated the usefulness of EECP in selected patients, these guidelines permit recommendations for the extended application of this important treatment to subsets of patients excluded from clinical trials.

Aged↗
PubMed2006

Long-term mortality, cause of death, and temporal trends in complications after percutaneous aortic balloon valvuloplasty for calcific aortic stenosis.

We sought to assess survival, predictors of adverse outcomes, and complication rates in a more recent series of adults undergoing percutaneous aortic balloon valvuloplasty (PABV) for symptomatic calcific aortic stenosis. While aortic valve replacement is the treatment of choice for adults with symptomatic calcific aortic stenosis, PABV has been used in selected patients who are not good surgical candidates. Registries of patients who underwent PABV over 15 years ago have shown poor long-term survival and high procedural complication rates. This single-center cohort study enrolled consecutive adults undergoing PABV between 1989 and 2005 for calcific aortic stenosis. Demographic, hemodynamic, and procedural data, as well as vital status, were collected by chart review and query of the National Death Index. The study included 78 patients: mean age 78 +/- 11 years, 51% female, 90% heart failure, 61% coronary disease, and 8% end-stage renal disease. While 22% had a major procedural complication, this rate tended to decrease over time (P=0.068). In the cohort, 87% died with a median survival of 6.6 months. According to NDI records, the primary cause of death was cardiac in 54% of deaths. Survival was significantly higher in patients <or=70 years and those bridged to aortic valve replacement. PABV in patients who are elderly and not candidates for bridge to aortic valve replacement is associated with poor long-term survival. The decrease in the complication rate over the past 15 years has important implications regarding the morbidity associated with percutaneous aortic valve replacement techniques.

Adult↗
PubMed2005

Association between phonocardiographic third and fourth heart sounds and objective measures of left ventricular function.

CONTEXT: The third (S3) and fourth (S4) heart sounds detected by phonocardiography are considered to represent the criterion standards of the gallop sounds, but their test characteristics have not been explored. OBJECTIVE: To determine the diagnostic test characteristics of the S3 and S4 for prediction of left ventricular dysfunction using a computerized heart sound detection algorithm. DESIGN, SETTING, AND PARTICIPANTS: Prospective study of 90 adult patients undergoing elective left-sided heart catheterization at a single US teaching hospital between August 2003 and June 2004. The mean age was 62 (SD, 13) years (range, 24-90 years) and 61 (68%) were male. Within a 4-hour period, participants underwent computerized heart sound phonocardiographic analysis, cardiac catheterization, transthoracic echocardiography, and blood sampling for assessment of an S3/S4, left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP), respectively. MAIN OUTCOME MEASURES: Diagnostic test characteristics of the computerized phonocardiographic S3 and S4 using markers of left ventricular function as criterion standards. RESULTS: Mean (SD) LVEDP was significantly elevated (18.4 [6.9] mm Hg vs 12.1 [7.3] mm Hg; P<.001), mean (SD) LVEF was reduced (49.4% [20.2%] vs 63.6% [14.8%]; P<.001), and median (interquartile range) BNP was elevated (330 [98-1155] pg/mL vs 86 [41-192] pg/mL; P<.001) in those with an S3, S4, or both compared with patients without a diastolic heart sound. The sensitivities of these heart sounds to detect an elevated LVEDP, reduced LVEF, or elevated BNP were 41%, 52%, and 32% for an S3, and 46%, 43%, and 40% for an S4, respectively. For abnormal levels of the same markers of ventricular function, the specificities of the S3 were 92%, 87%, and 92%, while the specificities of the S4 were 80%, 72%, and 78%, respectively. CONCLUSIONS: Neither the phonocardiographic S3 nor the S4 is a sensitive marker of left ventricular dysfunction. The phonocardiographic S3 is specific for left ventricular dysfunction and appears to be superior to the moderate specificity of the phonocardiographic S4.

Adult↗
PubMed2005

Effects of intravenous levosimendan on human coronary vasomotor regulation, left ventricular wall stress, and myocardial oxygen uptake.

BACKGROUND: Levosimendan is a calcium-sensitizing agent and an inodilator under current investigation in the treatment of decompensated heart failure. The effects of intravenous levosimendan on the human coronary vasculature, together with myocardial wall stress and oxygen uptake, have not been adequately studied. METHODS AND RESULTS: Ten adult patients underwent right- and left-heart catheterization. Baseline coronary blood flow was determined with quantitative coronary angiography and an intracoronary Doppler-tipped guidewire. Myocardial oxygen uptake was measured with a coronary sinus catheter. Echocardiography was performed before and 30 minutes after an intravenous infusion of levosimendan (24-microg/kg bolus over 10 minutes) was begun. Pulmonary capillary wedge decreased 37% (P=0.009), cardiac output increased 9% (P=0.04), and systemic vascular resistance decreased 18% (P<0.001). Left ventricular ejection fraction increased 20% (P=0.009), and meridional systolic wall stress decreased 48% (P=0.009). Coronary artery diameter increased 10% at 15 minutes (P=0.001) and 11% at 30 minutes (P=0.01). Coronary artery velocity increased 10% over baseline (P=0.04). Coronary blood flow increased 45% (P=0.02), whereas coronary resistance decreased 36% at 30 minutes (P=0.03). Myocardial oxygen extraction decreased 9% at 30 minutes (P=0.04). CONCLUSIONS: Levosimendan given intravenously exerts vasodilator effects on human coronary conductance and resistance arteries. Despite a decrease in coronary perfusion pressure, coronary blood flow is increased. A reduction in coronary vascular resistance and a decrease in coronary venous oxygen content indicate primary coronary vasodilation by levosimendan. Improved left ventricular systolic function and decreased myocardial oxygen extraction suggest improved myocardial efficiency.

Adult↗
PubMed2005

Frequency and efficacy of repeat enhanced external counterpulsation for stable angina pectoris (from the International EECP Patient Registry).

We assessed the frequency, efficacy, predictors, and long-term success of repeat enhanced external counterpulsation (EECP) therapy in relieving angina in a large cohort of patients who had chronic angina pectoris and had undergone a full course of EECP. Within 2 years of the initial course of EECP, the rate of repeat EECP was 18%, which occurred at a mean interval of 378 days after initial EECP. Of those who underwent repeat EECP, 70% had a decrease of >/=1 angina class at the end of repeat EECP with similar decreases in nitroglycerin use.

Aged↗
PubMed2005

Randomized study of the safety and clinical utility of rotational vs. standard coronary angiography using a flat-panel detector.

The purpose of this study was to test the hypothesis that rotational angiography improves patient safety while maintaining diagnostic accuracy for patients undergoing coronary angiography. Despite advances in angiographic technique, patients remain at risk for complications of coronary angiography, including contrast-induced nephropathy and radiation exposure. Technology has been developed to perform coronary angiography with active rotation of the imaging system that may reduce the quantity of contrast and radiation to which the patient is exposed. Fifty patients undergoing diagnostic cardiac catheterization were randomized to either standard vs. rotational angiography of the coronary arteries using a prespecified protocol with a flat-panel single-plane imaging system. We measured the quantity of radiographic contrast utilized and radiation exposure. Using an intention-to-treat analysis, there was a 40% reduction (24 +/- 5 vs. 40 +/- 10 ml; P < 0.0001) in contrast utilization in the rotational group compared to the standard group. Neither radiation exposure (35 +/- 14 vs. 30 +/- 20 Gycm(2); P = 0.35), fluoroscopic time (44 +/- 33 vs. 44 +/- 40 sec; P = 0.99), nor procedure time (249 +/- 137 vs. 214 +/- 79 sec; P = 0.26) differed, although significant intraoperator variability was noted for both standard and rotational angiography. The radiation exposure using this flat-panel system is significantly lower than prior reports that used an image intensifier system. Rotational coronary angiography has the potential to improve patient safety by markedly reducing radiographic contrast exposure while maintaining comparable diagnostic accuracy, radiation exposure, and procedure time compared to standard coronary angiography.

Adolescent↗
PubMed2005

The effects of enhanced external counterpulsation on myocardial perfusion in patients with stable angina: a multicenter radionuclide study.

BACKGROUND: Enhanced external counterpulsation (EECP) reduces angina and extends time to exercise-induced ischemia in patients with symptomatic coronary disease. One- and two-center studies and a retrospective case series reported that EECP improves myocardial perfusion in stable angina pectoris. We sought to critically evaluate and quantify the effect of EECP on myocardial perfusion. METHODS: In 6 US university hospitals, EECP was performed for 35 hours in patients with class II to IV angina who had exercise-induced myocardial ischemia. Symptom-limited quantitative gated technetium Tc 99m sestamibi single photon emission computed tomography exercise perfusion imaging was performed at baseline and 1 month post-EECP. Sestamibi was injected at the same heart rate in both stress tests. Single photon emission computed tomography images were read at a blinded core laboratory. RESULTS: Thirty-seven patients were enrolled, 34 of whom completed pre- and post-EECP stress testing. The mean age was 61 +/- 10 years, 81% were male, 78% had prior revascularization, and 68% had 3-vessel disease. The mean angina class decreased from 2.7 +/- 0.7 at baseline to 1.7 +/- 0.7 after EECP (P < .001). Exercise duration increased from 9.1 +/- 3.7 minutes at baseline to 10.2 +/- 3.6 minutes post-EECP (P = .03). The average percentage of tracer uptake, magnitude of reversibility, average thickening fraction, and the left ventricular ejection fraction remained unchanged after EECP. CONCLUSIONS: We confirm previous report that EECP reduces angina and improves exercise capacity. There were no significant changes in mean defect magnitude, amount of reversibility, thickening fraction, and ejection fraction measured using myocardial quantitative single photon emission computed tomography imaging when compared at identical pre- and post-EECP heart rates.

Angina Pectoris↗
PubMed2005

Effects of intravenous nesiritide on pulmonary vascular hemodynamics in pulmonary hypertension.

BACKGROUND: Nesiritide is effective in the treatment of decompensated heart failure (HF). We evaluated the acute hemodynamic effects of nesiritide, a recombinant B-type natriuretic peptide, in patients with HF and pulmonary hypertension (PH). METHODS AND RESULTS: Twenty patients with HF and PH (mean pulmonary arterial [PA] pressure >25 mm Hg) were enrolled: 10 with postpulmonary capillary wedge (PCW) >15 mm Hg and 10 with precapillary PH (PCW) < or =15. The pulmonary and systemic hemodynamics were determined by right heart catheterization at baseline and at 15 and 30 minutes after an intravenous nesiritide infusion (2 mcg/kg bolus and 0.01 mcg.kg.min). For the patients with postcapillary PH, the mean left ventricular ejection fraction was 28 +/- 15%. After the 30-minute nesiritide infusion, right atrial (RA) pressure decreased 48% (P < .0001), mean PA pressure decreased 29% (P < .0001), PCW pressure decreased 40% (P < .0001), cardiac index (CI) increased 35% (P = .009), pulmonary vascular resistance index (PVRI) decreased 35% (P = .01), and arteriovenous oxygen difference (AVDO(2)) decreased 27% (P = .0003). For precapillary PH patients, there was no change in RA, PA, or PCW pressure, nor any change in CI, PVRI, or AVDO(2). CONCLUSIONS: Nesiritide acutely and significantly reduced PA pressure, PVRI, and biventricular filling pressures in patients with postcapillary PH. However, for patients with precapillary PH, nesiritide had no significant acute hemodynamic effect on the pulmonary hemodynamics. The lack of acute beneficial effects of nesiritide in patients with advanced precapillary PH may be related to their relatively fixed remodeling of the pulmonary vasculature.

Adult↗