Suzanne Rodler

Novel Insights Into the Mechanisms and Treatment of Intramural Hematoma Affecting the Entire Thoracic Aorta

BACKGROUND The purpose of this study was to address a previously not described mechanism underlying intramural hematoma (IMH) of the entire thoracic aorta and to test the hypothesis whether endovascular stent graft placement in this particular mechanism could be beneficial. METHODS Within a 5-year period, we treated 8 patients with IMH affecting the entire thoracic aorta. The presumed site of initial plaque rupture was chosen as target for endovascular stent graft placement. RESULTS In all patients, a small atherosclerotic plaque at the free lateral wall or at the concavity of the distal aortic arch could be identified as initial site of IMH. Endovascular stent graft placement was performed successfully in all patients. By covering the suspected primary lesion, resorption of IMH especially within the ascending aorta could be achieved. Mean follow-up is 16 months (range, 1 to 25). CONCLUSIONS Plaque rupture may be identified as the cause of IMH in a previously unrecognized subgroup of patients. If at the convexity of the distal arch, supra-aortic branches prevent retrograde extension toward the ascending aorta. If at the free lateral wall or at the concavity, IMH may affect the entire thoracic aorta, owing to the lack of the natural barrier of the supra-aortic branches. Endovascular stent graft placement of this plaque-associated IMH may be more effective and less invasive than conventional surgery to treat the entire thoracic aortic disease.

Regular physical exercise improves endothelial function in heart transplant recipients

Background: Impaired endothelial function is detectable in heart transplant (HTX) recipients and regarded as risk factor for coronary artery disease. We have studied whether endothelial function can be improved in HTX patients participating in a regular physical training program as demonstrated in patients with chronic heart failure, hypertension and coronary artery disease.

Bridging to heart transplantation: prostaglandin E1 versus prostacyclin versus dobutamine

BACKGROUND Prostaglandin E1 (PGE1) and prostacyclin have potent pulmonary and systemic vasodilating properties. This prospective, randomized trial compared PGE1 vs prostacyclin vs. low-dose dobutamine in patients with low-output heart failure awaiting heart transplantation (HTx) who were refractory to oral treatment. METHODS Patients in advanced heart failure in New York Heart Association (NYHA) Class IV, with a cardiac index < or = 2.5 L/minute/m2 and a pulmonary capillary wedge pressure > or = 20 mmHg, who were listed for HTx were studied. In an inpatient study phase of 12 hours duration, therapy was aimed to increase cardiac output by 20% or more, when compared to baseline values, and to achieve a reduction of pulmonary vascular resistance below 550 dyn.s/cm-5m-2. During a long-term outpatient phase, the drugs were continuously infused to bridge these patients to HTx using three combined negative endpoints (worsening heart failure, serious adverse events, death) for analysis. RESULTS Sixty-eight patients were enrolled, 30 patients on PGE1, 8 patients on prostacyclin, and 30 patients on dobutamine. During the inpatient study phase, maximum doses were 22 +/- 1.8 ng/kg/minute for PGE1, 7 +/- 1 ng/kg/minute for prostacyclin and 5 +/- 0.4 micrograms/kg/minute for dobutamine. During the inpatient study phase 21 patients failed, 4/30 (13%) patients on PGE1, 4/8 patients on prostacyclin (50%), and 13/30 (43%) on dobutamine (p < 0.05). Long-term continuous intravenous drug infusion in outpatients was begun in 26 patients on PGE1, in 4 patients on prostacyclin, and in 17 patients on dobutamine. Infusion therapy lasted for 88 +/- 14 days in the PGE1 group with 31 +/- 22 days in the prostacyclin group, and 30 +/- 8 days in the dobutamine group (NS). During the outpatient phase 23 patients reached a negative endpoint with 16 patients developing worsening heart failure, 5 severe adverse events and 2 deaths. Seven out of 26 (27%) failed on PGE1, 4/4 (100%) failed on prostacyclin, and 12/17 (71%) failed on dobutamine (p < 0.05, log rank test). Because prostacyclin treatment was ineffective in the first 8 patients, this trial arm was stopped prematurely. CONCLUSIONS The findings from this prospective open pilot trial suggest that continuous PGE1 infusions at individualized dosages can be useful in certain patients as a pharmacologic bridging procedure with reduced risk to develop worsening heart failure before HTx compared to prostacyclin and dobutamine. Further comparative studies are warranted to investigate the effects of PGE1 among other bridging agents.

Five-Year Follow-up After Heart Valve Replacement With the CarboMedics Bileaflet Prosthesis

BACKGROUND The CarboMedics valve is a relatively new, low-profile, bileaflet, mechanical prosthesis. The results of a prospective follow-up study after valve replacement with this prosthesis in a university hospital are presented. METHODS We implanted 640 CarboMedics prostheses in 583 patients in the aortic (n = 359), mitral (n = 167), or aortic and mitral positions (double valve replacement; n = 57). Patient ages ranged from 11 to 81 years (mean age, 58 +/- 12.3 years). RESULTS Overall hospital mortality was 9.0%; however, when high-risk urgent cases were removed from the calculation, the operative mortality fell to 4.5%. Follow-up was 98% complete, comprising 2,027 patient-years for a mean follow-up of 44 months (range, 6 to 72 months). Actuarial freedom from complications (linearized rates in parentheses) was as follows: late mortality, 85% +/- 2.0% (2.3%/patient-year); thromboembolism, 92% +/- 1.1% (1.6%/patient-year); anticoagulation-related hemorrhage, 87% +/- 1.2% (2.8%/patient-year); prosthetic valve endocarditis, 98% +/- 0.5% (0.1%/patient-year); and overall valve-related morbidity and mortality, 76% +/- 2.1% (4.3%/ patient-year). CONCLUSIONS The CarboMedics valve shows a low rate of valve-related complications comparable with other new mechanical heart valve prostheses.

Beneficial hemodynamic effects of prostaglandin E1 infusion in catecholamine-dependent heart failure: results of a prospective, randomized, controlled study.

ObjectiveTo study the hemodynamic effects of prostaglandin E1: (PGE1)administered in addition to a standard catecholamine infusion in patients with severe chronic heart failure. DesignProspective, placebo-controlled, randomized, single-blind study. SettingIntensive care unit at a university hospital. PatientsThirty patients with severe chronic heart failure, New York Heart Association functional class TV (28 men, two women, with a mean age of 54 ± 2 yrs, mean left ventricular ejection fraction 10 ± 0.6%). All patients received oral therapy with digitalis, furosemide (mean dose 300 ± 46 mg/day), and enalapril (20 ± 2.7 mg/day). InterventionsHemodynamic measurements using pulmonary artery flotation catheters were performed at baseline, ≥24 hrs after standardized catecholamine infusion with dopamine (3 μg/kg/min) and dobutamine (5 μg/kg/min), as well as 48 hrs after randomization to infusion therapy with PGE1 (30 μg/kg/min) or a placebo. Measurements and Main ResultsThe addition of PGE1 to an ongoing catecholamine infusion in 20 patients caused a 16 ± 4% decrease in mean pulmonary arterial pressure (p < .001), a 22 ± 5% decrease in pulmonary artery occlusion pressure (p < .0001), a 24 ± 8% decrease in pulmonary vascular resistance index (p < .001), a 20 ± 9% decrease in right atrial pressure (p < .01), a 14 ± 3% decrease in mean arterial pressure (p < .001), and a 29 ± 4% decrease in systemic vascular resistance index (p < .0001). These PGE1- induced decreases occurred without a change in heart rate.Stroke volume index increased with PGE1 therapy by 34 ± 7% (p < .0001), and cardiac index increased by 34 ± 6% (p < .0001). No hemodynamic changes were observed during combined infusion with catecholamines and placebo in ten patients. ConclusionPGE1 improves the hemodynamic state in end-stage chronic heart failure patients already receiving a standard dose dopamine/ dobutamine infusion. (Crit Care Med 1994; 22:1084–1090)

Six-year follow-up after heart valve replacement with the Edwards Duromedics bileaflet prosthesis.

The Duromedics Edwards valve (DE) was designed with a self-irrigating hinge mechanism to reduce the rate of thromboembolic complications. This report presents a prospective follow-up of patients after valve replacement with this prosthesis in a university hospital. Five hundred seven patients had DE prostheses implanted in the aortic (n = 268), mitral (n = 183) or aortic and mitral positions (n = 56). The perioperative mortality was 6.9%. Follow-up was 98% complete, comprising 2009 patient years for a mean follow-up of 48 months: (range 27-84). The actuarial freedom from complications is calculated as follows (linearized rates in parentheses): late mortality 81.0 +/- 2.3% (3.4%/patient year), thromboembolism 93.5 +/- 1.5% (1.1%/patient year), anticoagulation-related hemorrhage 89.5 +/- 2.0% (1.9%/patient year), prosthetic valve endocarditis 96.0 +/- 1.2% (0.7%/patient year), valve-related mortality 93 +/- 1.8% (1.5%/patient year), valve failure 89 +/- 2.0% (2%/patient year), treatment failure 88.0 +/- 2.0% (2.2%/patient year) and all valve-related morbidity and mortality 74.0 +/- 2.8% (5.3%/patient year). Two events of leaflet escape were observed in the study group (0.09%/patient year). Both patients were reoperated successfully. Mechanical hemolysis was subclinical in all cases. The DE shows a complication rate comparable to other modern mechanical valve prostheses. After solving the problem of durability, reconsideration of this valve is worthwhile due to its low risk of thromboembolic complications.

Intimal hyperplasia and coronary flow reserve after heart transplantation: association with big endothelin-1

BACKGROUND Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.