Nifedipine treatment for pulmonary hypertension in a patient with systemic sclerosis

[Pulmonary hypertension associated with connective tissue diseases]

PURPOSE

Pulmonary hypertension is a rare but well-known life-threatening complication of connective tissue diseases. The aim of this article is to analyse the available literature and to report the experience of a pulmonary vascular diseases centre about this complication.

CURRENT KNOWLEDGE AND KEY POINTS

Scleroderma and its limited variant, the CREST syndrome (calcification, Raynaud phenomenon, esophageal dysmotility, sclerodactily, telangiectasia), is the most common connective tissue disease affected by pulmonary hypertension. Dyspnea is the main symptom and is frequently severe. Echocardiography is an excellent exam to detect pulmonary hypertension. However, right heart catheterization is necessary to confirm the diagnosis of pulmonary hypertension and to test vasoreactivity with a potent vasodilator such as nitric oxide. Pulmonary hypertension is less severe in patients with connective tissue diseases perhaps because of an earlier diagnosis. A significantly lower proportion of patients presents an acute vasodilator response, suggesting an early constitution of irreversible pulmonary vascular lesions. Continuous intravenous epoprostenol therapy seems to be less effective as compared with patients with primitive pulmonary hypertension and does not improve survival. So, we observed dramatic improvement in rare cases after immunosuppressive therapy.

FUTURE PROSPECTS AND PROJECTS

New treatments with oral, subcutaneous or inhaled stable prostacyclin analogs or with an endothelin receptor antagonist are currently being evaluated. The role of immunosuppressive therapy has to be defined.

Clinical trials in pulmonary hypertension

Progress in treatment of pulmonary hypertension has been impaired by the lack of formal clinical trials. This is now beginning to change, and the impact on our approach to treating patients with pulmonary hypertension in substantial. As with other relatively uncommon medical disorders, randomized, controlled, multi-center trials are needed to assess the safety and efficacy of potential therapeutic modalities. Treatments showing promise at the level of small pilot studies within a single center should be studied more rigorously.

Acute hemodynamic responses to inhaled nitric oxide in patients with limited scleroderma and isolated pulmonary hypertension

BACKGROUND

Inhaled nitric oxide (NO) is a selective pulmonary vasodilator that reduces pulmonary vascular resistance (PVR) in patients with primary pulmonary hypertension. Their responses to inhaled NO predict their responses to other vasodilators, such as prostacyclin, and provide an estimate of the "fixed" component of their increased PVR. Some patients with limited cutaneous systemic sclerosis develop isolated pulmonary hypertension with a similar clinical course. Therefore, we have measured the acute hemodynamic response to inhaled NO in such patients.

METHODS AND RESULTS

Seven patients were studied during inhalation of increasing concentrations of NO (0 to 80 ppm). Complete hemodynamic data were collected on five patients. They demonstrated a selective, dose-dependent, and rapidly reversible fall in PVR (34%) and mean pulmonary artery pressure (17%). There was a nonsignificant increase in cardiac index but no change in mean arterial pressure or systemic vascular resistance. The mean right atrial pressure fell (27%), but there was no change in pulmonary artery occlusion pressure. Of the seven patients, five responded to inhaled NO ( < or = 40 ppm) with a decrease in total pulmonary resistance of at least 20%.

CONCLUSIONS

Inhaled NO is an effective and selective pulmonary vasodilator in a significant number of patients with pulmonary hypertension associated with limited cutaneous systemic sclerosis. It may be useful in determining the potentially reversible contribution to the increased PVR and should be considered for patients with acute pulmonary vascular crisis.

Long-term iloprost infusion therapy for severe pulmonary hypertension in patients with connective tissue diseases

OBJECTIVE

To determine the effects of short-term, maximum-tolerated-dose and long-term, optimum-dose iloprost treatment of severe pulmonary hypertension associated with systemic sclerosis (SSc) and the primary antiphospholipid syndrome (APS).

METHODS

Three patients with SSc and 2 with APS who had failed to respond to oral vasodilator therapy for pulmonary hypertension were enrolled in a 32-week, open, prospective trial. Short-term infusion of maximum-tolerated doses and continuous infusion of optimum doses of iloprost were carried out following baseline cardiac catheterization. Catheterization was repeated at 2 and 32 weeks. All 5 patients completed the study and continued therapy for an average of 82 weeks (range 58-103).

RESULTS

Acute infusion of maximum tolerated doses significantly ameliorated the cardiac index (0.92 liters/minute/m2; P < 0.01), pulmonary artery O2 saturation (10.6%; P < 0.05), and pulmonary resistance (-6.7 units; P < 0.05). After 2 weeks of continuous infusion of optimum doses, there was improvement in pulmonary resistance (> or = 16%) and pulmonary artery O2 saturation (> 30%) in the 2 patients with primary APS. After 2 and 32 weeks, the 3 SSc patients showed variable hemodynamic responses. New York Heart Association functional class and exercise tolerance improved in all patients. There was 1 episode of bacteremia, and 1 patient died after 72 weeks of study.

CONCLUSION

Continuous iloprost infusion may improve exercise tolerance and quality of life in patients with severe pulmonary hypertension associated with SSc and primary APS.

Pharmacotherapy of chronic pulmonary arterial hypertension: value and limitations. Part II: Secondary pulmonary hypertension

Part I of this review discussed pharmacotherapy of primary pulmonary hypertension (PHT). Part II describes the value and limitations of oxygen and vasodilator therapy of secondary PHT, focusing on patients with PHT associated with selected connective tissue disease and chronic nonthrombotic hypoxic lung disease.

Short- and long-term hemodynamic effects of captopril in patients with pulmonary hypertension and selected connective tissue disease

To assess the pulmonary and systemic hemodynamic effects of oral captopril in patients with connective tissue disease and pulmonary hypertension, we performed right heart catheterization in eight patients with diffuse systemic sclerosis, the CREST syndrome, or mixed connective tissue diseases prior to and immediately following administration of captopril (dose range 12.5 to 50.0 mg, short-term study). Four of these patients underwent repeat right heart catheterization after three to six months of oral captopril therapy (long-term study). In the short-term study, oral captopril produced a significant decrease in mean pulmonary vascular resistance from 6.2 +/- 3.6 to 4.6 +/- 3.8 units (p < 0.01). This was accompanied by a significant decrease in mean pulmonary artery pressure, mean blood pressure, mean systemic vascular resistance and a significant increase in cardiac output. Similar changes in pulmonary hemodynamics were noted in the long-term study. Thus, oral captopril is capable of producing an acute and sustained reduction in pulmonary vascular resistance in patients with pulmonary hypertension associated with the aforementioned connective tissue diseases.

Acute and long-term effects of nifedipine on pulmonary and systemic hemodynamics in patients with pulmonary hypertension associated with diffuse systemic sclerosis, the CREST syndrome and mixed connective tissue disease

Ten patients with pulmonary hypertension associated with diffuse systemic sclerosis (1 patient), the CREST syndrome (calcinosis cutis, Reynaud's phenomenon, esophageal dysmotility, sclerodactyl, telangiectasia) (6 patients) and mixed connective tissue disease (3 patients) were studied to assess the effect of oral nifedipine on pulmonary and systemic hemodynamics. Each patient underwent right-sided cardiac catheterization just before nifedipine administration. Thereafter, oral nifedipine was administered in 10 mg increments every 90 minutes until pulmonary vascular resistance normalized or a total dose of 30 mg was achieved. Hemodynamic measurements were obtained at 30-minute intervals for 3 hours, then hourly for 9 hours (acute study). Hemodynamic studies were repeated 3 to 6 months after the initial catheterization with the minimum dose of oral nifedipine (administered every 8 hours) required to achieve maximal reduction of pulmonary vascular resistance in the acute study (long-term study). In the acute study, oral nifedipine produced a significant decrease in mean pulmonary vascular resistance from 6.3 +/- 3.8 to 4.3 +/- 3.6 U (p less than 0.001). Similar changes in pulmonary vascular resistance were noted in the long-term study (n = 6). The results indicate that oral nifedipine is capable of producing an acute and sustained reduction in pulmonary vascular resistance in patients with pulmonary hypertension associated with diffuse systemic sclerosis, the CREST syndrome and mixed connective tissue disease.

Nifedipine and prazosin in the management of pulmonary hypertension in CREST syndrome

A 62-year-old woman with CREST syndrome and isolated pulmonary hypertension (without evidence of interstitial lung disease) underwent right heart catheterization to evaluate the effect of steroid and vasodilator treatment on hemodynamic parameters. During 12 weeks of prednisone treatment in a dosage of 40 mg daily, her condition markedly deteriorated clinically and hemodynamically as manifested by pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR), cardiac output (CO), mixed venous O2 saturation, and systemic vascular resistance (SVR). Successive trials with various vasodilators demonstrated ineffectiveness of isosorbide dinitrate and phenoxybenzamine, whereas nifedipine was effective in a 15-mg single dose, and prazosin 1 mg was partially effective in reducing PVR, SVR, and increasing CO and mixed venous O2 saturation. The combination of nifedipine 10 mg and prazosin 0.5 mg given alternately every four hours for 48 hours was the most effective in reducing PVR and PAP. Clinical response was favorable as well until treatment with medications was discontinued due to gastrointestinal side effects one month later.

Value and limitations of calcium channel blockade in the treatment of pulmonary hypertension associated with CREST--case reports

Reversible vasospasm has been hypothesized to underlie the development of pulmonary hypertension in patients with CREST. Drugs that prevent arterial spasm have been used to treat pulmonary hypertension with variable results. The disparate pulmonary hemodynamic responses to calcium channel blockade reported herein suggest that CREST patients with mild pulmonary hypertension may have a component of reversible vasospasm responsive to vasodilator therapy, whereas patients with moderate to severe pulmonary hypertension may have fixed vessel lesions precluding a satisfactory response to calcium channel blockade.

Noninvasive evaluation of cardiac dysrhythmias, and their relationship with multisystemic symptoms, in progressive systemic sclerosis patients

Fifty-three patients (34 who had diffuse scleroderma, and 19 who had CREST syndrome [calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasias]) were studied by noninvasive procedures, including resting electrocardiogram (ECG), continuous 24-hour Holter ECG monitoring, M-mode echocardiography, and 2-dimensional echocardiography. Only 22 patients (42%) had abnormalities such as conduction defects, supraventricular or ventricular arrhythmias, or ST-T changes detected on resting ECG. In contrast, using Holter monitoring, the number of conduction abnormalities seen increased from 10 to 16 patients and transient ST-T changes increased from 2 to 18 patients. Forty-eight patients had ventricular arrhythmias, with multiform ventricular premature beats in 21 (40%), pairs of runs of ventricular tachycardia in 15 patients (28%), and 1 or more runs of ventricular tachycardia in 7 (13%). Echocardiography detected asymmetric septal hypertrophy in 10 patients, impaired ventricular function in 9 patients, congestive cardiomyopathy in 2, mitral prolapse in 4, and pericardial effusion in 3 patients. Multiform and/or repetitive ventricular premature beats occurred more frequently in patients with echocardiographic abnormalities, but were also present in patients who had normal findings on echocardiographic examination. Cardiac involvement was not correlated with clinical variants of scleroderma (CREST syndrome or diffuse scleroderma), nor with other signs and symptoms of the disease. Thus, cardiac involvement is found much more frequently than would be expected from clinical symptoms or from results of resting ECG alone; therefore, Holter monitoring and echocardiography should be included in the routine workup of patients who have scleroderma.

Promising uses of calcium-channel blocking agents

It is not surprising that calcium-channel blocking agents, which have numerous effects on various physiologic systems, have been employed for several "unapproved" uses. This manuscript reviews reports that have appeared within the last two years describing unapproved cardiovascular and noncardiovascular uses of the three available calcium-channel blocking agents. The cardiovascular uses discussed include hypertensive emergencies, pulmonary hypertension, congestive heart failure, aortic insufficiency, Raynaud's phenomenon, migraine headaches, antiplatelet effects and cardiac surgery. Areas of noncardiovascular use include muscular dystrophy, achalasia, esophageal spasm, dysmenorrhea, preterm labor, asthma, hyperuricemia, mania and depression and endocrinologic and oncologic conditions. While some of the data appear promising, other reports are conflicting and contradictory. Furthermore, because much of the information comes from poorly controlled trials or anecdotal reports, even the more promising uses must be studied further and compared with conventional therapy.