Prospective evaluation of pulmonary artery pressures during pulmonary angiography performed with low-osmolar nonionic contrast media

Complications of right heart catheterization procedures in patients with pulmonary hypertension in experienced centers

OBJECTIVES

This study sought to assess the risks associated with right heart catheter procedures in patients with pulmonary hypertension.

BACKGROUND

Right heart catheterization, pulmonary vasoreactivity testing, and pulmonary angiography are established diagnostic tools in patients with pulmonary hypertension, but the risks associated with these procedures have not been systematically evaluated in a multicenter study.

METHODS

We performed a multicenter 5-year retrospective and 6-month prospective evaluation of serious adverse events related to right heart catheter procedures in patients with pulmonary hypertension, as defined by a mean pulmonary artery pressure >25 mm Hg at rest, undergoing right heart catheterization with or without pulmonary vasoreactivity testing or pulmonary angiography.

RESULTS

During the retrospective period, 5,727 right heart catheter procedures were reported, and 1,491 were reported from the prospective period, for a total of 7,218 right heart catheter procedures performed. The results from the retrospective and the prospective analyses were almost identical. The overall number of serious adverse events was 76 (1.1%, 95% confidence interval 0.8% to 1.3%). The most frequent complications were related to venous access (e.g., hematoma, pneumothorax), followed by arrhythmias and hypotensive episodes related to vagal reactions or pulmonary vasoreactivity testing. The vast majority of these complications were mild to moderate in intensity and resolved either spontaneously or after appropriate intervention. Four fatal events were recorded in association with any of the catheter procedures, resulting in an overall procedure-related mortality of 0.055% (95% confidence interval 0.01% to 0.099%).

CONCLUSIONS

When performed in experienced centers, right heart catheter procedures in patients with pulmonary hypertension are associated with low morbidity and mortality rates.

Safety and Hemodynamic Effects of Pulmonary Angiography in Patients with Pulmonary Hypertension: 10-Year Single-Center Experience

OBJECTIVE

We sought to examine the incidence of complications and change in pulmonary artery pressure in patients with pulmonary hypertension who were undergoing pulmonary angiography.

MATERIALS AND METHODS

A retrospective review was performed for all patients who underwent pulmonary angiography over a 10-year period at a single institution. Patients with moderate pulmonary hypertension (pulmonary artery pressure, 30-59 mm Hg) and severe pulmonary hypertension (pulmonary artery pressure, >/= 60 mm Hg) served as the study population. Demographic data, clinical indication, pre- and postcontrast pulmonary artery pressure measurements, type of pulmonary hypertension, contrast agent volume, complications, and American Society of Anesthesiologists (ASA) classification were recorded for all patients and compared.

RESULTS

Two hundred two of 612 patients who underwent pulmonary angiography had pulmonary hypertension. Moderate pulmonary hypertension was present in 155 patients (77%) and severe pulmonary hypertension, in 47 patients (23%). Three (2.0%) of four complications were fatal. The complication rate was higher in patients with severe pulmonary hypertension compared with patients with moderate pulmonary hypertension but not statistically significant (6.3% vs 0.6%, p = 0.63). Patients with complications had a higher mean ASA score than those without complications (4.0 vs 3.0, p = 0.03). Patients with lung transplants had the greatest increase in pulmonary artery pressure after pulmonary angiography compared with all other clinical indications (16.75 +/- 12.97 mm Hg vs 5.46 +/- 6.86 mm Hg, p = 0.003).

CONCLUSION

The complication rate of pulmonary angiography in patients with pulmonary hypertension is low. However, in severely ill patients with acute pulmonary hypertension, pulmonary angiography should be undertaken with extreme caution.

Current strategies for the diagnosis of pulmonary embolus

Venous thromboembolic disease (VTD), comprising venous thrombosis and pulmonary embolus, is responsible for innumerable deaths every day. Wide variance in its presentation and clinical manifestations and the resultant difficulties in achieving its diagnosis have confounded attempts to define optimal diagnostic and treatment strategies. Those strategies should be predicated on the understanding of the manifestations of VTD and of the attributes and interrelationship of the various modalities available for its diagnosis. This review will present an overview of the literature describing those modalities, their strengths and deficiencies, and their current value in algorithms for the diagnosis of VTD.

Acute and delayed outcomes of mechanical thrombectomy with use of the steerable Amplatz thrombectomy device in a model of subacute inferior vena cava thrombosis

PURPOSE

To study the efficacy and delayed outcome of mechanical thrombectomy with the Amplatz thrombectomy device (ATD) in an experimental model of subacute inferior vena cava (IVC) thrombosis.

MATERIALS AND METHODS

Mechanical thrombectomy was performed in 23 dogs with subacute infrarenal IVC thrombosis (6-15 days old). Heparin was administered during thrombectomy in all procedures (activated clotting time > or = 300 sec). Thirteen animals were killed immediately after thrombectomy, and the remaining 10 were allowed to survive for up to 1 month with no anticoagulation therapy.

RESULTS

Venographic patency of the IVC was restored in all animals, although residual mural thrombus remained in nine dogs (< 20% narrowing in seven, 20%-30% narrowing in two). No histopathologic evidence of mechanical wall disruption attributed to mechanical thrombectomy was seen. However, foci of organizing residual thrombus with associated transmural phlebitic changes with round-cellular infiltration were present in all acute specimens, including those appearing clear at venography. Venography at 1 week or 1 month after thrombectomy showed IVC rethrombosis in eight dogs (80%) who were not receiving anticoagulants. During mechanical thrombectomy, a small increase in mean pulmonary artery pressure occurred, with a corresponding decrease in systemic arterial oxygen saturation. No acute emboli were noted on the post-thrombectomy pulmonary angiograms. However, histopathologic examination of acutely explanted lungs in 11 animals showed arteriolar microemboli (100-500 microm) in four.

CONCLUSION

Mechanical thrombectomy with use of the ATD can effectively clear subacute IVC thrombus. However, rethrombosis is common and may be due to the high prevalence of phlebitis and residual thrombus. Anticoagulation may need to be continued after successful thrombectomy to prevent progression of residual thrombus and allow mural phlebitic changes to subside.