Stein Iversen

Mid-term results of pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension

BACKGROUNDnIn patients with chronic thromboembolic pulmonary hypertension, acute and striking decreases of pulmonary artery pressures and vascular resistance can be achieved by pulmonary thromboendarterectomy. In this study, the long-term effects of pulmonary thromboendarterectomy on hemodynamic indices and right ventricular function were investigated.nnnMETHODSnSixty-five patients (31 women and 34 men; mean age, 47 +/- 17 years; range, 19 to 69 years; New York Heart Association [NYHA] functional class II, n = 3; class III, n = 38; class IV, n = 24) were reassessed 13 to 48 months (mean, 27 months) after pulmonary thromboendarterectomy. Measurements are reported as mean +/- standard deviation.nnnRESULTSnAll patients reported a significant improvement of symptoms: 46 patients were in NYHA functional class I, 16 patients in class II, and 3 patients in class III. Mean pulmonary vascular resistance was significantly reduced compared with preoperative and postoperative values (preoperative: 1,015 +/- 454 dynes.s.cm-5; postoperative: 322 +/- 154 dynes.s.cm-5; follow-up: 198 +/- 72 dynes.s.cm-5; p < 0.001 versus preoperative; p < 0.025 versus postoperative). Concomitantly, cardiac index was significantly increased compared with preoperative values (preoperative: 2.0 +/- 0.7 L.min-1.m-2; follow-up: 2.9 +/- 0.5 L.min-1.m-2; p < 0.001). Significant reductions of right ventricular dimensions and recovery of right ventricular function could be demonstrated radiologically and echocardiographically. In 3 patients (preoperative NYHA class IV, NYHA class III at follow-up) with proven coagulation abnormalities, pulmonary vascular resistance was moderately increased at follow-up compared with postoperative measurements.nnnCONCLUSIONSnIn patients with chronic thromboembolic pulmonary hypertension, a persistent decrease of pulmonary vascular resistance and improvement of right ventricular function and NYHA functional status can be achieved by pulmonary thromboendarterectomy.

Detection of Central Pulmonary Artery Thromboemboli by Transesophageal Echocardiography in Patients with Severe Pulmonary Embolism

Transthoracic echocardiography generally provides only indirect signs of pulmonary embolism. In contrast, with transesophageal echocardiography the thromboembolus itself can be visualized in the central parts of the pulmonary artery. The aims of our study were to evaluate, first, the incidence of central pulmonary artery thromboemboli in patients with severe pulmonary embolism, and second, the accuracy of the echocardiographic diagnosis. Our study group comprised 60 patients with proved severe pulmonary embolism. All patients were examined by transthoracic and transesophageal echocardiography. The echocardiographic findings concerning the absence or presence of central pulmonary artery thromboemboli were compared with the results of different reference methods. Central pulmonary thromboemboli were found in 35 patients (58.3%) by echocardiography. Two types of thrombus were differentiated. Type A is a long, highly mobile thrombus, and type B is an immobile wall-adherent thrombus. In comparison with the reference methods, we determined a sensitivity of 96.7% and a specificity of 88% for the echocardiographic detection of central pulmonary artery thromboemboli in patients with severe pulmonary embolism. Transesophageal echocardiography seems to be a useful method for the diagnosis of severe pulmonary embolism. In our series, central pulmonary artery thromboemboli were present in more than half of the patients. In these cases, transesophageal echocardiography can clarify the diagnosis within a few minutes without further invasive diagnostic procedures.

Surgical Treatment of Myocardial Bridging Causing Coronary Artery Obstruction

Nine patients with obstruction of coronary artery blood flow caused by myocardial bridging underwent surgery after failure of medical treatment. The diagnoses were made angiographically at rest or during beta-stimulation. Impaired blood flow was found only in the left anterior descending artery in seven patients and additionally in the diagonal branch in two. The operations, performed with cardiopulmonary bypass consisted of complete dissection of the overlying myocardium. All patients survived the operation. Major intraoperative complications were accidental opening of the right ventricle in two patients. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation. Surgical relief of myocardial ischemia due to systolic compression of intramyocardial coronary arteries can be accomplished with low operative risk and with excellent functional results.

Troponin T: a reliable marker of perioperative myocardial infarction?

Following cardiac surgery, electrocardiography and creatine kinase isoenzyme MB (CK-MB) activities are of limited value in diagnosing a non-transmural infarction. With the recent availability of an assay to detect serial levels of the specific cardiocyte contractile protein troponin T the possibility has been increased of closing a diagnostic gap among cardiosurgical patients. Ninety patients with severe diffuse three-vessel disease undergoing myocardial revascularization were grouped by their postoperative electrocardiographic (ECG) findings (group I--unchanged ECG; group II--new Q-waves representing perioperative myocardial infarction (PMI)). Serial levels of troponin T and the activity of CK-MB were measured 6, 12, 24 and 48 h after aortic unclamping. The course of CK-MB activity was compared to a profile and values derived from patients with unchanged (n = 1312) or new Q-wave ECGS (n = 89). In 72 patients (80.0%) with unchanged postoperative ECG (group I) serial troponin T levels remained constantly low and reached a median peak value of 0.37 microgram/l (quartile 0.13-0.50 microgram/l) after 24 h. Serial CK-MB activities demonstrated the typical non-ischemic course with a monoexponential decline from an initial median peak value of 15.5 U/l (quartile 12.0-21.0 U/l) to 7.0 U/l (quartile 6.0-9.0 U/l). In seven patients (7.8%) with new Q-waves and a pathologic CK-MB profile (group II) troponin T reached median levels of 10.47 micrograms/l (quartile 6.34-12.50 micrograms/l) (P < 0.001 I vs II). Four of five patients with a new right bundle branch block demonstrated low troponin T levels below 1 microgram/l and a normal CK-MB profile. Among six patients with unchanged QRS-configuration and elevated troponin T levels between 0.84 and 4.99 micrograms/l CK-MB activity showed a characteristic PMI pattern in two patients. Troponin T is characterized by a very narrow margin of normal values represented by a maximum third quartile of 0.50 microgram/l. A singular value of troponin after 6 h or 24 h may be sufficient evidence to confirm the diagnosis of a PMI.

Value and Limitations of Transesophageal Echocardiography in the Evaluation of Aortic Prostheses

Results of 34 transesophageal (TEE) studies in patients with suspected aortic prosthetic dysfunction were compared with transthoracic echocardiographic (TTE) results and to anatomic findings. Mass lesions noted at surgery (autopsy) were correctly described in 93% by TEE versus 43% by TTE. Abscesses were detected in 88% by TEE versus 18% by TTE. Bioprosthetic degeneration was visualized in 88% versus 38% and prosthetic obstruction correctly identified in 75% versus 50% by TEE and TTE, respectively. Anatomic aortic regurgitant lesions were identified in 96% by TEE versus 77% by TTE, whereas the correct origin was detected in 88% of cases by TEE versus 54% of cases by TTE. TEE provides valuable additional information on morphologic conditions and flow pathology in aortic valve prostheses.

Diagnosis of perioperative myocardial necrosis following coronary artery surgery ― a reappraisal of isoenzyme analysis

Although the routine determination of CK-MB activity is widely used after coronary artery bypass grafting (CABG), the diagnosis of a perioperative myocardial necrosis remains arbitrary. The intention of the present study was to develop discriminative enzymatic parameters of CK-MB activity in a collective of 710 patients following CABG. Patients were grouped according to their postoperative electrocardiogram (ECG). For each patient, the time activity curve of CK-MB was determined. The total amount of CK-MB was calculated by integrating the area beneath the CK-MB activity curve. Patients presenting with an unchanged postoperative ECG (group I) or a new bundle branch block with uncompromised haemodynamics (group IIa) had an uniform and low profile of CK-MB activity. Serial CK-MB activities as well as the integrated CK-MB area of these two collectives were significantly different (P less than 0.001) from values determined for patients with bundle branch block and low cardiac output (group II b) or patients with new Q waves (group III). After 24h, the 90th percentile of serial CK-MB activities of group I had declined to 18 U/l and was clearly exceeded by 90% of all patients that belonged to either group IIb or III. The 90th percentile of CK-MB areas for group I showed a value of 801 U/l x h. CK-MB areas above 801 U/l x h were seen in about 50% of all patients of group IIa.(ABSTRACT TRUNCATED AT 250 WORDS)

Sarcoma of the pulmonary artery: Report of two cases and a review of the literature

SummaryPrimary tumours of the pulmonary arteries are rare neoplasms seldom diagnosed during the patients life time. We report on two cases of pulmonary artery sarcomas diagnosed during life time of the respective patients in intra-operative frozen sections by histopathological examination. Case 1 was of a 55-year-old man with a fibrosarcoma originating from the main pulmonary trunk. Case 2 was of a 43-year-old woman with a malignant fibrous histiocytoma originating from the right pulmonary artery. In both patients a radical tumour resection under cardiopulmonary bypass was attempted. Both patients, however, had a local tumour recurrence and died 18 months (patient 1) and 6 months (patient 2) after surgery. A review of pulmonary artery sarcomas is given.

Endoventricular patch plasty improves results of LV aneurysmectomy.

From May 1985 to December 1991 52 patients were operated upon for postischemic left ventricular aneurysm (LV-A). Between May 1985 and July 1989 25 patients (group I) with a mean age of 59 (46-72) years underwent conventional aneurysmectomy with direct closure of the left ventricle (LV) and a mean of 1.9 (0-3) additional bypass grafts (54% triple-vessel disease). The hospital mortality was 8% (2/25) and the late mortality during a median follow-up time of 34 months was 28% (7/25) with a 4-year survival of 66%. Improvement in the quality of life (NYHA from 2.6 to 2.1, P = 0.078) and global left ventricular ejection fraction (EF) (from 35 to 38%) proved to be unsatisfactory in conjunction with the high late mortality rate. Between August 1989 and December 1991 a prospective series of 27 consecutive patients (group II) with a mean age of 61 (45-71) years underwent endoventricular patch plasty guided by two-dimensional transthoracic echocardiography (TTE) before and after surgery. The patch size and position were calculated preoperatively by measuring the distances from the mitral annulus to the infarct area which were reproduced during surgery with a simple ruler. A mean of 2.1 (0-4) bypass grafts were added with 62% of the patients having triple-vessel disease and 19% left main stenosis (P = 0.05, group I versus II). All patients have survived to date. One patient had to be excluded, giving a median follow-up time of 14 months for 26 patients. At the 6 months control, the mean NYHA class was improved from 2.7 to 1.6, (P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Resection of central primary pulmonary artery sarcoma

Primary sarcomas of the pulmonary arteries are rare, and the diagnosis is in the majority of the reported cases established postmortem. Surgical resection of these centrally located tumors has been performed either by pneumonectomy and/or local tumor resection. We report on two patients with sarcomas of the central pulmonary arteries who underwent successful resection of the tumor and prosthetic replacement of the arteries under cardiopulmonary bypass. One patient required additional thromboendarterectomy of the right pulmonary artery branches because of secondary thrombus formation. As primary pulmonary artery sarcomas are refractory to both chemotherapy and radiation, surgical resection remains the only means of treatment. The prognosis depends entirely upon resectability, which, if necessary, should be performed with the aid of cardiopulmonary bypass. In this way, lung resection may be avoided.

Urgent indications for surgery in primary or secondary cardiac neoplasm

Ten patients underwent resection of primary or secondary cardiac tumor. Two-dimensional transthoracic echocardiography per se accurately located the endoluminal cardiac mass in nine patients, and transesophageal echocardiography demonstrated a right atrial tumor in the tenth case. The indications for urgent surgery included prior embolic events (3 cases), syncopal attacks (2) or echocardiographic evidence of a multilobulated mass (2 cases). The operative strategy was standardized for atrial tumors, but for malignant myocardial neoplasm both the anatomic site and the extent of tumor growth determined the surgical procedure. Histologic examination showed myxoma in seven cases, fibroma in one and metastases of malignant melanoma in two cases. The course after resection of endoluminal benign tumor was uneventful apart from transient atrial fibrillation in four cases. Follow-up echocardiography (after 4-28 months) showed no recurrent growth. In both cases of intracardiac metastases there was recurrence within 6 to 8 months after resection of the growth.