Echocardiographic features of primary pulmonary hypertension

The ratio of the atrial areas reflects the clinical status of patients with pulmonary arterial hypertension

PURPOSE

Echocardiography is useful not only for detecting pulmonary hypertension (PH) but also for estimating the severity of PH by evaluating various morphological changes of the heart caused by pressure and volume overload and by ventricular interaction. We investigated whether a novel echocardiographic index, i.e., the ratio of the atrial areas (RA/LA), would be useful for evaluating the clinical status of patients with pulmonary arterial hypertension (PAH) treated with intravenous epoprostenol.

METHODS

We introduced epoprostenol therapy for seven PAH patients without severe tricuspid regurgitation. We evaluated clinical criteria indicative of prognosis, for example World Health Organization functional class (WHO-FC), brain natriuretic peptide (BNP) level, echocardiographic indices such as indexed RA area and RA/LA, and hemodynamics before and one year after intravenous epoprostenol therapy.

RESULTS

There were significant improvements in both RA/LA (2.5 ± 1.0, 1.3 ± 0.4, P < 0.001) and indexed RA area (22.5 ± 8.9, 14.5 ± 5.8, P < 0.001). The improvement in RA/LA was more sensitive than that in indexed RA area (P < 0.01). Moreover, RA/LA was significantly correlated with WHO-FC (r = 0.50, P < 0.01) and BNP level (r = 0.82, P < 0.01).

CONCLUSIONS

RA/LA is useful for evaluating the clinical status of patients with PAH treated with intravenous epoprostenol.

Beneficial and adverse effects of bosentan treatment in korean patients with pulmonary artery hypertension

Background and Objectives

The purpose of this study was to investigate 1) the beneficial effect of bosentan treatment (125 mg twice daily) on exercise capacity and echocardiographic variables and 2) the profiles and frequency of adverse events in Korean patients with World Health Organization (WHO) class III or IV pulmonary artery hypertension (PAH).

Subjects and Methods

Twelve patients who received bosentan treatment were investigated in an open label manner. One patient was excluded in the final analyses due to a prohibited concomitant medication. A 6-minute walk test and echocardiography were performed at baseline and after 12 weeks of treatment.

Results

The administration of bosentan for 12 weeks resulted in a significant improvement in exercise capacity (measured with the 6-minute walking distance), WHO functional capacity, and in echocardiographic variables. Bosentan treatment was associated with a decrease in the maximal tricuspid regurgitation jet velocity {from 4.7 m/sec (95% confidence interval, 3.89-5.45) at baseline to 4.4 m/sec (95% confidence interval, 3.61-5.1) at 12 weeks, p=0.03} and systolic pulmonary arterial pressure {from 105 mmHg (95% confidence interval, 74.4-135.6) at baseline to 93 mmHg (95% confidence interval, 66.3-120.1) at 12 weeks, p=0.04}. Treatment with bosentan at a dose of 125 mg twice a day was not associated with life-threatening side effects, although a higher incidence of elevated liver enzymes compared to previous studies was noted.

Conclusion

Bosentan at a dose of 125 mg twice daily is considered a clinically optimal, safe dose and can be used as a valuable treatment option in Korean PAH patients with WHO functional capacity III or IV, though close monitoring of liver function is required.

Pulmonary hypertension caused by sarcoidosis

Pulmonary hypertension is an uncommon complication of sarcoidosis, but in severe pulmonary disease it occurs frequently. It is an important cause of cryptogenic dyspnea in sarcoidosis patients and can occur despite the absence of pulmonary fibrosis. The true prevalence is unknown. With the advent of specific therapies for pulmonary hypertension, there has been a resurgence of interest in the pathophysiology, diagnosis, and treatment of sarcoidosis-associated pulmonary hypertension. This article reviews the status of the current epidemiologic, pathophysiologic, and therapeutic knowledge regarding this entity.

Role of radial strain and displacement imaging to quantify wall motion dyssynchrony in patients with left ventricular mechanical dyssynchrony and chronic right ventricular pressure overload

Left ventricular (LV) deformation with ventricular septal shift is one of the most distinctive echocardiographic observations in patients with chronic right ventricular (RV) pressure overload (PO). However, little is known about the effects of RVPO on LV performance and regional synchrony. Accordingly, our objective was to test the hypothesis that chronic RVPO affects regional wall motion, synchronicity, and global LV function using a novel speckle-tracking approach to quantify and characterize regional LV wall motion dyssynchrony. Displacement and strain imaging echocardiographic studies were performed in 20 patients with RVPO from pulmonary arterial hypertension or pulmonic stenosis (mean age 53 +/- 16 years, New York Heart Association class 2.6 +/- 0.7, and peak RV systolic pressure 73 +/- 28 mm Hg) and 20 age-matched normal subjects (mean age 47 +/- 16 years). Segmental signals from 6 segments around the mid-LV short axis were defined as dyssynchronous if their changes were opposite to that of the global LV signal at each time frame, and overall LV dyssynchrony was calculated as the percentage of dyssynchrony in all 6 segments within the specified time interval from onset of QRS to the end of isovolumic relaxation. RVPO was associated with a large degree of regional dyssynchrony with paradoxical ventricular septal motion observed by displacement imaging (21 +/- 6%, p <0.05 vs control group), which was closely associated with LV eccentricity index (r = 0.79, p <0.05) and LV myocardial performance index with linear regression (r = 0.76, p <0.05). In contrast, strain imaging showed uniform segmental radial thickening in the RVPO group, which was similar to the control group, and suggests that there was no intrinsic LV contractile dyssynchrony. In conclusion, LV wall motion dyssynchrony assessed by displacement imaging, not intrinsic contractile dyssynchrony by strain imaging, coexists with LV chamber deformation with ventricular septal shift and is closely associated with impairment of LV performance.

Echocardiographic and right heart catheterization techniques in patients with pulmonary arterial hypertension

BACKGROUND

The cardiovascular assessment of patients with suspected pulmonary arterial hypertension (PAH) involves Doppler echocardiography and often subsequent confirmation by right heart catheterization (RHC). However, there appears to be limited consensus on the appropriate technique(s) for assessing PAH, and thus no clear, comprehensive guidelines exist for assessment of PAH. The aim of this paper is to review the Doppler echocardiographic and RHC techniques for the diagnosis and/or assessment of PAH.

METHOD

We searched Medline (1966 to August 2006) and EMBASE (1980 to August 2006) bibliographic databases to allow identification of all potentially relevant studies and review articles. In addition, the reference lists of included articles were scanned to identify relevant references and unpublished reports missed by the search strategy.

RESULTS

Our findings show that recommendations for the echocardiographic assessment of PAH at rest or with exercise are heterogeneous. Clinical practice guidelines provide limited details. Although more specific information regarding echocardiographic techniques can be obtained from individual research articles, the techniques employed and the methods used to calculate specific hemodynamic variables do not appear to be consistent throughout the literature. RHC techniques for the confirmation of PAH are more consistent, albeit less frequently reported. The literature search identified several articles where indications and considerations for the catheterization of patients with PAH are discussed, together with safety considerations and principles for the accurate assessment of hemodynamic variables.

CONCLUSION

Although clinical practice guidelines and numerous research studies provide details of echocardiographic measures in patients with PAH, greater consensus and standardisation of measurement techniques is required. A minimum dataset for the evaluation of PAH by these techniques is suggested.

Pulmonary hypertension in the critical care setting: classification, pathophysiology, diagnosis, and management

Pulmonary hypertension (PH) is common in the critical care setting, and may be a target for specific therapy. Moderate degrees of pulmonary hypertension are most often the consequence of acute or chronic heart failure, hypoxemia, or acute pulmonary embolism, and may be relatively rapidly reversible. The consequences of more severe forms of PH, both acute and chronic, can include hypotension; low cardiac output; right heart failure with congestion of the liver, gut, and kidneys; and varying degrees of hypoxemia, each of which can lead to death or severe disability. We review the physiology, definitions, classification, pathogenesis, diagnostic tools, and algorithms for diagnosis and specific treatments for the various causes of PH as seen in the critical care setting.

A rabbit model with acute thrombo-embolic pulmonary hypertension created with echocardiography guidance

A rabbit model of acute thrombo-embolic pulmonary hypertension was developed by infusing self-thrombi into the right femoral vein and simultaneously measuring the pulmonary artery pressure via a right heart catheter and echocardiography. The model was used to explore the usefulness of an ultrasound-guided protocol. In the present study, acute thrombo-embolic pulmonary hypertension was produced in 25 of 30 healthy New Zealand rabbits; the success rate was 83%. A significant and positive correlation between the right ventricle-right atrial pressure gradient, an estimate of the pulmonary artery systolic pressure derived from tricuspid regurgitation and the pulmonary artery systolic pressure measured using the right heart catheter (r=0.765, P=0.002) was noted. During the process of establishing a rabbit model of acute thrombo-embolic pulmonary hypertension, it was demonstrated that echocardiography can be used to guide the right heart catheter to obtain pulmonary artery systolic pressure measurements, to quantify the tricuspid regurgitation jet to assess the pulmonary artery systolic pressure and to observe cardiac morphologic changes so as to evaluate cardiac function. Based on the present study, it is clear that echocardiography is valuable in improving the success rate of producing the animal model of acute thrombo-embolic pulmonary hypertension. This could ultimately facilitate preclinical research and clinical research in humans.

Imaging of the heart in pulmonary hypertension

Pulmonary hypertension (PH) is a disease of the pulmonary arteries resulting in a progressive increase in pulmonary vascular resistance, ultimately leading to right ventricular failure and death. It is a rare disease with a poor prognosis. The functional capacity of the right ventricle (RV) is a major prognostic determinant in PH. Our understanding of RV performance in PH has been hindered by the lack of techniques that give a reliable picture of right ventricular morphology and function. There have been recent major advances in our understanding of the mechanism of disease development, in the diagnostic process and in the treatment of PH. There are now three classes of medications that are effective in the treatment of PH: prostanoids, endothelin receptor antagonists and phosphodiesterase-5 inhibitors. Therapeutic advances in the management of PH have reinforced the requirement for non-invasive, accurate and reproducible methods of assessment to act as 'end-points' to measure the effects of treatment. It is our opinion that the most useful 'end-point' would be one that evaluates right heart morphology and function. We introduce and discuss the techniques currently used to image the heart in patients with PH. Imaging modalities discussed include echocardiography, radionuclide ventriculography, cardiac computed tomography and cardiac magnetic resonance (CMR) imaging focusing on the rapidly evolving technique of CMR imaging.

Doppler echocardiographic assessment of the effects of inhaled long-acting β2-agonists on pulmonary artery pressure in COPD patients

Increase in pulmonary artery pressure (PAP), which is common in severe chronic obstructive pulmonary disease (COPD), is a predictor of mortality independent of airflow limitation. beta-agonists might slightly attenuate this increase because they exert a vasodilating effect on pulmonary circulation when systematically administered. We have investigated the acute effects of salmeterol and formoterol on echocardiographic systolic pulmonary artery pressure (sPAP) in 20 patients with COPD and a sPAP greater than 20mmHg at rest. Acute haemodynamic responses to inhaled formoterol or salmeterol were assessed in all patients, in a randomized, double-blind double-dummy fashion. On two consecutive days, patients received, in a randomized order, formoterol 12microg via Turbuhaler plus placebo via Diskus or salmeterol 50microg via Diskus plus placebo via Turbuhaler. Transthoracic Doppler echocardiography measurements of sPAP were made before and 15, 30, 60 and 180min after bronchodilator inhalation. Lung function, pulse oximetry and heart rate were also monitored at the same times. Mean sPAP significantly (p<0.05) decreased in comparison with baseline at 15, 30, and 60min post inhalation but returned towards control levels at 180min after both salmeterol and formoterol. There was no correlation between the maximum increase in FEV(1) and maximum decrease in sPAP either after inhalation of salmeterol (r(2)=0.071) or after that of formoterol (r(2)=0.0006). The increases in FEV(1) in comparison with baseline were always significant (p<0.05) from 15 to 180min post inhalation after either salmeterol or formoterol. Neither pulse oximetry nor heart rate changed in a significant manner (p>0.05). This study demonstrated that salmeterol and formoterol were equally beneficial for pulmonary haemodynamics in patients with COPD. A direct vasodilatation due to the activation of beta-adrenoceptors that are present in pulmonary vessels is a likely mechanism of their action in inducing the decrease in sPAP.

Diagnosis of pulmonary arterial hypertension

Accurate diagnosis of pulmonary arterial hypertension is a challenging and complex process that requires a high index of clinical suspicion from even the most astute clinician. This article discusses the use of a variety of noninvasive tests that can help define the population of patients in whom invasive cardiac catheterization should be pursued. It points out the vagaries and limitations of electrocardiography and the radiographic and echocardiographic clues to the diagnosis. Ultimately, right- and, often, concomitant left-heart catheterization is required to establish the diagnosis and distinguish pulmonary arterial hypertension from pulmonary venous hypertension.

Pulmonary arterial hypertension: evaluation and management

Pulmonary arterial hypertension (PAH), a rare disease involving the pulmonary vascular circuit, is defined as an elevation in pulmonary arterial pressures and is characterized by symptoms of dyspnea, chest pain, and syncope. If left untreated, the disease carries a high mortality rate, with the most common cause of death being decompensated right heart failure. Over the past 5 years, there have been significant advances in this field in regards to understanding the pathogenesis, diagnosis, and classification of PAH. The availability of newer drugs has resulted in a radical change in the management of this disease with significant improvement in both quality of life and mortality. Ongoing research promises to lead to a more comprehensive understanding of the genetics, etiology, and pathogenesis of pulmonary arterial hypertension, which may ultimately translate into more effective therapeutic options.

Pericardial Abnormalities Predict the Presence of Echocardiographically Defined Pulmonary Arterial Hypertension in Systemic Sclerosis-Related Interstitial Lung Disease

OBJECTIVES

To determine the prevalence and significance of pericardial abnormalities in systemic sclerosis (SSc)-related interstitial lung disease (ILD).

METHODS

Retrospective study of 41 subjects with SSc-related ILD who underwent evaluation including thoracic high-resolution CT (HRCT) imaging, transthoracic echocardiography (TTE), and pulmonary function testing. HRCT review evaluated the pericardium for the presence of pericardial effusion (PEf), thickness of the anterior pericardial recess (APR) [abnormal defined as > 10 mm], and pericardial thickening as calculated by total pericardial score (TPS) [abnormal defined as > 8 mm]. Pulmonary arterial hypertension (PAH) was defined as a pulmonary artery pressure > 35 mm Hg estimated by TTE.

RESULTS

Fifty-nine percent had an abnormal pericardium, 49% had a PEf, 56% had an abnormal APR, and 49% had an abnormal TPS. An abnormal pericardium was more common in men than women. Subjects with and without pericardial abnormalities were otherwise similar with respect to age, SSc classification, autoantibodies, ILD radiographic pattern, and presence of esophageal dilation. Both groups had similar median percentage of predicted total lung capacity, percentage of predicted FVC, percentage of predicted FEV(1), and percentage of predicted diffusion capacity of the lung for carbon monoxide. Subjects with pericardial abnormalities were more likely to have coexistent PAH (35% vs 75%; p = 0.02) and a higher median right ventricular systolic pressure (31 mm Hg vs 44 mm Hg; p = 0.03). Multiple logistic regression revealed that TPS was the best individual predictor of the presence of TTE-defined PAH.

CONCLUSIONS

In patients with SSc-related ILD, pericardial abnormalities are commonly seen on HRCT, and their presence is strongly associated with echocardiographically defined PAH, with abnormal TPS as the best individual predictor.

Conversion to bosentan from prostacyclin infusion therapy in pulmonary arterial hypertension: a pilot study

STUDY OBJECTIVES

We assessed the efficacy of bosentan in transitioning from prostacyclin infusions in patients with pulmonary arterial hypertension (PAH).

METHODS

Twenty-two PAH patients were recruited from five PAH centers if they had been clinically stable while receiving therapy with IV epoprostenol or subcutaneous treprostinil for at least 3 months. Patients were observed in an open-label prospective trial while bosentan was added to therapy, and then epoprostenol or treprostinil were tapered after 2 months.

RESULTS

Ten of the 22 patients were transitioned off prostacyclin infusion therapy after a mean (+/- SEM) duration of 6.1 +/- 1.2 months. Of those patients, seven patients have continued not receiving prostacyclin infusion therapy for a mean duration of 17.7 +/- 5.3 months, with no significant changes in pulmonary artery (PA) pressure estimated by echocardiography, World Health Organization (WHO)/New York Heart Association (NYHA) functional class, 6-min walk distance (6MWD), or Borg dyspnea score. The conditions of three patients deteriorated, necessitating the resumption of prostacyclin therapy, and two patients subsequently died. Twelve patients failed to transition or even lower the prostacylin infusion rate and had worsening of their WHO/NYHA functional class and estimated systolic PA pressures, and had a trend toward deterioration in their mean 6MWD (294 +/- 41 to 198 +/- 34 m, respectively; p = 0.2). Of these, two patients subsequently died. The baseline characteristics of those who transitioned successfully vs those who transitioned unsuccessfully were a lower prostacyclin infusion rate, and less severe elevations in the mean and estimated systolic PA pressures.

CONCLUSION

Transitioning from therapy with prostacyclin to bosentan is possible in some PAH patients, mainly in those receiving lower prostacyclin doses and having less pulmonary hypertension at baseline. Careful patient selection and close interim monitoring is needed because the conditions of patients can deteriorate, and they may not respond to the resumption of therapy with prostacyclin.

Screening, early detection, and diagnosis of pulmonary arterial hypertension: ACCP evidence-based clinical practice guidelines

Pulmonary arterial hypertension (PAH) occurs as an idiopathic process or as a component of a variety of disease processes, including chronic thromboembolic disease, connective tissue diseases, congenital heart disease, and exposure to exogenous factors including appetite suppressants or infectious agents such as HIV. This article reviews evidence for screening in susceptible patient groups and the approach to diagnosing PAH when it is suspected, and provides specific recommendations for applying this evidence to clinical practice.

Diagnosis and evaluation of the patient with pulmonary hypertension

The term pulmonary hypertension is as imprecise as the term heart failure. Elevation in pulmonary arterial pressure can be caused by heterogeneous processes with profoundly different treatment implications. Pulmonary hypertension can present at any age and across all demographic ranges. Despite major advances in pathogenesis and treatment for pulmonary arterial hypertension, the diagnosis of this life-threatening but treatable condition often remains delayed and incomplete. Because the presenting symptoms of pulmonary hypertension are nonspecific, a high index of suspicion is required for timely recognition. Accordingly, suspecting or recognizing pulmonary hypertension remains the first and critical hurdle in the diagnosis of pulmonary hypertension. This article reviews the stepwise approach necessary for an efficient and accurate diagnosis of pulmonary hypertension.

Plain film / MR imaging correlation in heart disease

This article reviews common cardiovascular pathologies that can be noted first on plain film when previously unsuspected, and then illustrates how cross-sectional imaging can provide the follow-up information needed to make a diagnosis. First reviewed are the normal cardiac structures and contours as seen on the plain film of the chest, followed by specific types of pathologies as seen in older adults; patients with lung cancer invading the heart, pericardium, or large vessels; and postsurgical and posttraumatic findings. Also provided is a review of non-cardiac-related areas of plain film and cross-sectional imaging correlation. It is hoped that the reader gains a better understanding and appreciation for the great value of cross-sectional imaging, and the power of the plain film in helping detect and recognize thoracic pathology.

Effects of the oral endothelin-receptor antagonist bosentan on echocardiographic and doppler measures in patients with pulmonary arterial hypertension

OBJECTIVES

The purpose of this study was to investigate the effects of bosentan (125 or 250 mg twice daily) on echocardiographic and Doppler variables in 85 patients with World Health Organization class III or IV pulmonary arterial hypertension (PAH).

BACKGROUND

Bosentan, an orally active dual endothelin-receptor antagonist, improves symptoms, exercise capacity, and hemodynamics in patients with PAH.

METHODS

Patients had primary pulmonary hypertension (84%) or PAH associated with connective tissue disease. Of these, 29 patients received placebo and 56 received bosentan (1:2 randomization). Six-minute walk tests and echocardiograms were performed at baseline and after 16 weeks of treatment.

RESULTS

Baseline characteristics were similar in the placebo and bosentan groups, and echocardiographic and Doppler findings were consistent with marked abnormalities of right ventricular (RV) and left ventricular (LV) structure and function that were due to PAH. The treatment effect on 6-min walking distance was 37 m in favor of bosentan (p = 0.036). Treatment effects of bosentan compared with placebo on other parameters were as follows: Doppler-derived cardiac index = +0.4 l/min/m(2) (p = 0.007), LV early diastolic filling velocity = +10.5 cm/s (p = 0.003), LV end-diastolic area = +4.2 cm(2) (p = 0.003), LV systolic eccentricity index = -0.12 (p = 0.047), RV end-systolic area = -2.3 cm(2) (p = 0.057), RV:LV diastolic areas ratio = -0.64 (p = 0.007), Doppler RV index = -0.06 (p = 0.03), and percentage of patients with an improvement in pericardial effusion score = 17% (p = 0.05).

CONCLUSIONS

Bosentan improves RV systolic function and LV early diastolic filling and leads to a decrease in RV dilation and an increase in LV size in patients with PAH.

Usefulness and limits of transthoracic echocardiography in the evaluation of patients with primary and chronic thromboembolic pulmonary hypertension

The aim of the study was to evaluate the potential usefulness of transthoracic echocardiography in differentiating patients with primary or chronic thromboembolic pulmonary hypertension and to define the capability of echocardiography to assess right-heart performance in such patients. Right-heart catheterization and ultrasound examination were performed in 111 patients with chronic thromboembolic pulmonary hypertension and in 31 patients with primary pulmonary hypertension. All echocardiographic and Doppler parameters were similar in primary and chronic thromboembolic pulmonary hypertension. A significant correlation was found between the tricuspid annular plane systolic excursion and the right ventricular fractional area change and thermodilution-derived right ventricular ejection fraction (P <.001 for both). Furthermore, different patterns of the pulsed Doppler flow velocity curve into the superior vena cava were associated with different right-heart hemodynamic profiles. In conclusion, in patients with chronic pulmonary hypertension transthoracic echocardiography portends meaningful information on the capability of the right heart to confront the increased afterload but it does not permit etiologic differentiation.

Serial noninvasive assessment of progressive pulmonary hypertension in a rat model

Current methods used to investigate pulmonary hypertension in rat models of the disease allow for only one to two measurements of pulmonary artery (PA) pressure in the life of a rat. We investigated whether transthoracic echocardiography can be used to assess the progression of pulmonary hypertension in rats at multiple time points. Serial echocardiographic measurements were performed over a 6-wk period on rats injected with monocrotaline (MCT) or placebo. Development of a midsystolic notch in the PA waveform, a decrease in the PA flow acceleration time (PAAT), an increase in right ventricular (RV) free-wall thickness, and the development of tricuspid regurgitation (TR) were observed as pulmonary hypertension developed. Changes in the PA waveform and PAAT began in week 3 of disease development as the PA systolic pressure (PASP) reached 25-30 mmHg according to right heart catheterization. The RV free-wall thickness increased significantly by week 5 (PASPs 40-50 mmHg). Development of quantifiable TR occurred in week 6 or at PASPs > 65 mmHg. A linear correlation was found between the PAAT and PASP in the range of 30-65 mmHg and between the RV-right atrial pressure gradient (derived from TR velocity) and PASP at pressures >65 mmHg, which enabled a noninvasive estimate of the PASP over a wide range of pressures based on these parameters. These data indicate that transthoracic echocardiography can be used for monitoring the progress of pulmonary hypertension in a rat model.

[Clinico-hemodynamic study and treatment of 44 patients with primary pulmonary hypertension]

BACKGROUND

Primary pulmonary hypertension is a poorly understood disease with a difficult treatment.

PATIENTS AND METHOD

Retrospective study of a series of 44 patients suffering from pulmonary hypertension who were studied in our center between 1992 and 2000.

RESULTS

At diagnosis, 6 (13%) patients were classified as having NYHA functional class I, 11 (25%) had class II, 25 (57%) had class III, and 2 had class IV. Mean pulmonary artery systolic pressure by echo-doppler was 92 (range: 43-154) mmHg. Basal right catheterization showed a mean (SD) pulmonary artery pressure of 58 (18) mmHg, total basal pulmonary resistances of 1679 (1,071) din/cm2 and cardiac index of 2.2 (1) 1/minute/m2. Five patients improved with anticoagulation and calcium channel blockers therapy. Since 1998, 11 patients had been treated with continuous endovenous epoprostenol, yet only 3 (27%) had significant clinical improvement. Survival at 5 years after diagnosis was 56%. At the end of study, 7 (70%) out of 10 patients who underwent pulmonary transplantation were alive (mean: 34, range: 3-62 months).

CONCLUSIONS

Pulmonary hypertension is a disease with a poor prognosis. However, treatment with prostaglandins and pulmonary transplantation may lead to encouraging results.

Current management of primary pulmonary hypertension

Primary pulmonary hypertension (PPH) is a rare disorder of the lung vasculature characterised by an increase in pulmonary artery pressure. Although the aetiology of this disease remains unknown, knowledge of the pathophysiology of the disease has advanced considerably. Diagnosis of PPH is largely by exclusion. The clinical symptoms associated with PPH are aspecific and similar to those seen in other cardiovascular and pulmonary diseases. Electrocardiography, echocardiography, pulmonary function tests, and a lung perfusion scan are necessary to exclude secondary forms of pulmonary hypertension and also help to confirm the diagnosis of PPH. A definite diagnosis of PPH is established by right-heart catheterisation which gives a precise measure of the blood pressure in the right side of the heart and the pulmonary artery, right ventricular function and cardiac output. Once a diagnosis of PPH is established, treatment involving drug therapy or surgery is commenced on the basis of the New York Heart Association functional class. Conventional treatment consists of lifetime administration of anticoagulants, oxygen, diuretics, and digoxin. Vasodilator therapy with calcium channel antagonists is indicated in patients who are 'vasoreactive' to acute vasodilator challenge as assessed by right-heart catheterisation. Promising results are obtained by continuous intravenous administration of epoprostenol (prostacyclin). Newer therapies for PPH include prostacyclin analogues, endothelin receptor antagonists, nitric oxide, phosphodiesterase-5 inhibitors, elastase inhibitors, and gene therapy. Surgical treatment consists of atrial septostomy, thromboendarterectomy, and lung or heart-lung transplantation.

The prognostic role of the ECG in primary pulmonary hypertension

BACKGROUND/RATIONALE

Doppler echocardiography and invasive hemodynamic parameters reflective of right ventricular failure are associated with a poor prognosis in patients with primary pulmonary hypertension (PPH). The aims of the present study were to examine whether ECG features in patients with PPH are associated with a decrease in survival, and to determine the value of the ECG in risk stratification.

METHODS/RESULTS

We analyzed the ECG, New York Heart Association (NYHA) class, and hemodynamic parameters in 51 untreated patients with PPH (88% women; mean age, 41.7 years; 79% NYHA classes III and IV) evaluated between 1992 and 1998. Subsequent treatment included epoprostenol in 37 patients, calcium channel blockers in 10 patients, epoprostenol and atrial septostomy in 2 patients, and lung transplant in 3 patients. As of 1999, 16 patients had died. Based on Kaplan-Meier estimates, median survival was > 6.5 years and estimated survival at 1 year, 3 years, and 5 years was 86%, 71%, and 57%, respectively. Significant predictors of decreased survival by Cox regression analysis include pulmonary vascular resistance (PVR; hazard ratio [HR], 1.11 per Wood unit), cardiac index (HR, 0.22 per L/min/m(2)), p wave amplitude in lead II (HR, 3.06 per mm), p > or = 0.25 mV in lead II (HR, 2.77), qR in V(1) (HR, 3.55), and World Health Organization criteria for right ventricular hypertrophy (HR, 4.26). After controlling for PVR, the HRs attributable to the ECG criteria were only slightly diminished. NYHA class and pulmonary artery pressures did not correlate with a decrease in survival.

CONCLUSIONS

ECG parameters reflective of physiologic and anatomic abnormalities in the right ventricle are associated with decreased survival in patients with PPH, and may be useful for deciding therapeutic choices including the timing for lung transplantation listing.

Diagnostic value of resting tricuspid regurgitation velocity and right ventricular ejection flow parameters for the detection of exercise induced pulmonary arterial hypertension

Our objectives were to evaluate resting tricuspid regurgitation velocity (TRV) and right ventricular outflow tract velocity curve (RVOTvc) profiles as markers for development of exercise induced pulmonary arterial hypertension (ExPHT). ExPHT is an elusive cause of dyspnea and fatigue. When present, Doppler echocardiography can detect and quantify elevated pulmonary pressure. However, the characteristics and diagnostic value of resting TRV and RVOTvc indices in patients with ExPHT have not been fully addressed. The study population consisted of 52 subjects (mean age 40.5 +/- 10.9, range 22-68 years) and was divided into three subsets as follows: 1. Patients (n = 22) with overt pulmonary hypertension (PHT), 2. Patients (n = 8) with ExPHT, 3. Healthy, asymptomatic volunteers (n = 22). RVOTvc indices included: Mean and peak velocity, systolic velocity time integral (VTI); velocity time integral at peak velocity (VTImax), acceleration time; ejection time. TRV was used as an index of pulmonary artery systolic pressure. There were significant differences between normals and ExPHT for TRV, acceleration time, VTI(Vmax). TRV and VTImax were predictive of EXPHT in a logistic regression model.

CONCLUSION

(1) Patients with ExPHT have distinct Doppler velocity patterns suggesting the presence of a compromised pulmonary vascular bed even with normal pulmonary pressure at rest. (2) TRV and RVOTvc indices have potential diagnostic value in the early detection of ExPHT.