Surgical closure of patent foramen ovale in patients with suspected paradoxical embolism: long-term results.

OBJECTIVE: It is thought that a patent foramen ovale (PFO) is the crucial mechanism in patients with suspected paradoxical embolism and cryptogenic stroke. It has been hypothesized that closure of the PFO would prevent further cerebrovascular incidents. We describe our early and late experience with surgical closure of the PFO in patients with paradoxical embolism. PATIENTS AND METHODS: Between May 1994 and December 2001, 33 patients (26 men, 7 women; mean age, 55.2 +/- 8.7 years; range, 37-74) underwent surgical closure of a PFO at our institution. All patients had preoperatively suffered from a stroke and/or a transient ischemic attack, after which echocardiography showed a PFO. Mean follow-up at 99 +/- 30 months (range, 10-111 months) was 100% complete. RESULTS: All patients survived the operative procedure. Early complications occurred in four patients (12%). Actuarial survival at 1, 5 and 8 years was 97 +/- 3%, 97 +/- 5% and 94 +/- 8%, respectively. At long-term follow-up all but two patients were alive. The deaths of these two patients were related to malignancy and ischemic heart disease, respectively. Two patients (6%) had suffered a residual cerebrovascular event after successful surgery. CONCLUSION: Surgical closure of PFO in patients with paradoxical embolism can safely be performed with a low risk of early mortality. Residual thromboembolic events were rare and in those few it occurred it did so with the interatrial septum being closed, indicating that in those patients the PFO was not the mechanism of the thromboembolic event in the first place.

Elevations in antidiuretic hormone and aldosterone as possible causes of fluid retention in the Maze procedure.

BACKGROUND: Reduced levels of atrial natriuretic peptide (ANP) has been suggested as a cause of fluid retention after combined Maze and valvular surgery. This study aimed to assess hormonal activation in the perioperative setting of isolated Maze procedures. METHODS: Changes in ANP, brain natriuretic peptide (BNP), antidiuretic hormone (ADH), aldosterone, and angiotensin II were measured in 16 patients (mean age 53+/-9 years) without concomitant heart disease undergoing the Maze (III) procedure. Ten matched patients (mean age 56+/-9 years) undergoing multivessel coronary artery bypass grafting served as controls. Measurements with hemodynamic correlates were obtained at baseline and after ventricular pacing (100 stimulations/minute), directly preoperatively, postoperatively and the first postoperative day. Weight gain and diuretic requirements were recorded. RESULTS: The major differences in hormonal response were significantly higher plasma levels of ADH (Maze preoperative 1.1+/-0.4, postoperative 24.9+/-16.7 pmol/L; controls preoperative 1.1+/-0.1, postoperative 3.7+/-3.5 pmol/L) and aldosterone (Maze preoperative 106+/-94, postoperative 678+/-343 pmol/L; controls preoperative 124+/-79, postoperative 171+/-93 pmol/L) in the Maze group on the first postoperative day (p < 0.001). Preoperative baseline plasma levels of ANP and pulmonary capillary wedge pressures (PCWP) were higher in the Maze group but this difference was abolished by pacing, and postoperatively, ANP levels changed in parallel to the PCWP in both groups. Diuretic requirements were significantly higher in the Maze group. CONCLUSIONS: Substantial increases in ADH and aldosterone were observed after the Maze procedure, indicating these hormones as important determinants in postoperative fluid retention. The role for ANP in this setting may be a less prominent than previously reported.

Postoperative stroke in cardiac surgery is related to the location and extent of atherosclerotic disease in the ascending aorta.

OBJECTIVES: The aim of the study was to evaluate the risk from calcified atheromas in the ascending aorta, and the extent and topography of the disease in the development of stroke after cardiac surgery. BACKGROUND: Postoperative stroke constitutes a serious problem in cardiac surgery, and atherosclerosis of the ascending aorta is an important risk factor. METHODS: Before surgical manipulation epiaortic echocardiographic ultrasound was performed to evaluate the ascending aorta in 921 consecutive patients undergoing cardiac surgery. The presence of calcification, location of atheroma, extent of the disease and clinical variables including postoperative stroke were recorded prospectively. RESULTS: A total of 26.2% of the patients had atherosclerosis of the ascending aorta, and in 44.4% of them more than one of 12 possible segments was involved. Logistic regression showed that atherosclerotic disease in the ascending aorta was the most important predictive factor for postoperative stroke. The incidence of stroke was 1.8% in patients without atherosclerotic disease of the ascending aorta, and 8.7% in patients with the disease (p < 0.0001). Diabetes mellitus was also a predictive factor (p = 0.04). A new and unique finding of this study was that the middle-lateral segment is an independent predictive factor for postoperative stroke, with a relative risk of 26% (p = 0.04). CONCLUSIONS: Patients with atheromatosis in the ascending aorta had an 8.7% incidence of postoperative stroke, in spite of minor surgical modifications. The risk depended on the presence, location and extent of the disease. Randomized trials evaluating alternative surgical strategies in coronary surgery are urgently needed in high risk patients.

Myocardial Doppler tissue velocity improves following myocardial gene therapy with VEGF-A165 plasmid in patients with inoperable angina pectoris.

BACKGROUND: Myocardial tissue velocity and perfusion were studied in patients with severe angina pectoris following gene therapy by intramyocardial injection of phVEGF-A165 via thoracotomy. Plasma concentrations of VEGF-A increased postoperatively. Two months after treatment anginal status and myocardial tissue velocity improved and perfusion showed a tendency to improve. Tissue velocity imaging appears to be a sensitive, objective method for detecting changes in myocardial function following gene therapy. OBJECTIVE: To study effects on myocardial tissue velocity and perfusion in patients with angina pectoris following intramyocardial injection of phVEGF-A165 via thoracotomy. DESIGN: Open label, phase I/II. METHODS: Six patients with Canadian Cardiovascular Society (CCS) angina pectoris functional class III - IV and with major defects at adenosine stress single-photon emission computerized tomography (SPECT) were studied. In addition to SPECT, coronary angiography and dobutamine stress echocardiography with tissue Doppler velocity imaging were performed before and two months after gene transfer. RESULTS: Plasma concentrations of VEGF-A increased 2 to 3 times (P < 0.04) over baseline from 2 to 14 days after injection with normalization after 4 weeks. The CCS class improved about 40%, from 3.3 +/- 0.2 to 2.0 +/- 0.3 (P < 0.02) and nitroglycerine consumption decreased 30 - 40%, from 44 +/- 17 to 15 +/- 5 tablets per week (P < 0.05). The maximal systolic myocardial tissue velocity increased in all patients about 25% (P < 0.02) but did not reach the reference range. Myocardial perfusion at SPECT improved in four of the six patients. CONCLUSIONS: Anginal status, myocardial tissue velocity and perfusion can be improved by phVEGF-A165 intramyocardial injection. Tissue velocity imaging appears to be a sensitive, objective method for detecting changes in myocardial function following gene therapy.

Transaortic approach for the Alfieri stitch.

The management of associated mitral regurgitation in patients undergoing cardiac surgery is controversial. A simple, reliable, and fast repair is advantageous, especially in critically ill patients. We describe a simple method of transaortic edge-to-edge repair in patients with associated mitral regurgitation undergoing aortic valve surgery.

Effects of intramyocardial injection of phVEGF-A165 as sole therapy in patients with refractory coronary artery disease--12-month follow-up: angiogenic gene therapy.

OBJECTIVE: To test the safety and bioactivity of phVEGF-A165 after intramyocardial injection during 12-month follow-up. DESIGN: Open-labelled study. SUBJECTS: Inclusion criteria were angina pectoris, Canadian Cardiovascular Society (CCS) class III-IV, unamenable to further revascularization, ejection fraction (EF) >30%, perfusion defects extending over >10% of the anterolateral left ventricle wall detectable with adenosine single photon emission computerized tomography (SPECT) and at least one patent vessel visible by coronary angiography. Seven of 39 patients referred for gene therapy were included. INTERVENTION: Via a mini-thoracotomy under general anaesthesia. phVEGF-A165 was injected directly into the myocardium at four sites in the anterolateral region of the left ventricle. RESULTS: Operative procedures were uneventful. Perioperative release of myocardial markers and electrocardiogram (ECG) changes were detected in two patients. There were no perioperative deaths but one patient died 7 months postoperatively because of myocardial infarction. Plasma vascular endothelial growth factor (VEGF)-A levels increased two to threefold peaking 6 days postoperatively (P < 0.004) and returning to baseline by day 30. A significant reduction in angina pectoris was reported. The CCS class improved from 3.3+/-0.2 to 1.9+/-0.3 (P < 0.01) and nitroglycerine intake decreased from 39+/-15 to 12+/-5 tablets week(-1) (P < 0.001) 2 months after gene transfer. Improvements remained after 12 months when nitroglycerine consumption approached zero. Improved myocardial function in the phVEGF-A165 injection region was documented in all patients (P < 0.016) by tissue velocity imaging (TVI). Reduced reversible ischaemia was detected by adenosine SPECT in four patients. Improved collateralization was detected in four patients with coronary angiography. CONCLUSION: Intramyocardial injection of phVEGF-A165 is safe and may lead to improved myocardial perfusion and function with longstanding symptomatic relief in end-stage angina pectoris. Based on these results this therapeutic potential is being tested in a double-blind placebo controlled multicentre trial.

Retrograde crystalloid cardioplegia preserves left ventricular systolic function better than antegrade cardioplegia in patients with occluded coronary arteries.

OBJECTIVE: To investigate retrograde and antegrade crystalloid cardioplegia in terms of cardiac cooling and postoperative cardiac function. DESIGN: Prospective, randomized, and blinded. SETTING: University hospital. PARTICIPANTS: Twenty male patients with triple-vessel disease and proximal occlusion of the circumflex or the left anterior descending coronary artery. INTERVENTIONS: Left ventricular ejection fraction at rest and during exercise was evaluated by nuclear ventriculography the day before and 3 months after surgery. After induction of anesthesia and hourly for the first 5 postoperative hours, hemodynamic, echocardiographic, and electrocardiographic data were acquired. Myocardial temperature was measured with needle thermistors in 3 myocardial regions. MEASUREMENTS AND MAIN RESULTS: Demographic and temperature data were analyzed by t-test. Hemodynamic and echocardiographic data were analyzed by analysis of variance. The groups were similar in baseline characteristics. Retrograde cardioplegia cooled the region distal to an occlusion better than antegrade cardioplegia (9.6 degrees C +/- 4.8 degrees C v 21.8 degrees C +/- 5.9 degrees C; p < 0.01). Hemodynamic, echocardiographic, and electrocardiographic data did not differ between the groups. Three months after surgery, the retrograde cardioplegia group showed a higher left ventricular ejection fraction at rest (58% +/- 10% v 47% +/- 10%; p < 0.02) and during exercise (58% +/- 13% v 47% +/- 10%; p < 0.05) compared with the antegrade cardioplegia group. CONCLUSIONS: Retrograde cardioplegia provides more homogenous myocardial cooling than antegrade cardioplegia in hearts with coronary artery occlusions. The use of retrograde cardioplegia seems to benefit long-term left ventricular function.

[Reconstructive heart surgery is possible also in severe heart failure]. / Rekonstruktiv hjärtkirurgi möjlig även vid svår hjärtsvikt.

Patients with severe heart failure due to valvular disease or coronary artery disease often benefit from conventional heart surgery even in the presence of severe left ventricular dysfunction. If a conventional procedure is not possible, left ventricular reconstructive surgery can be of value in selected cases. In cases of idiopathic dilated cardiomyopathy, the Batista procedure can improve left ventricular function, whereas in patients with ischemic cardiomyopathy, with or without left ventricular aneurysm, an endoventricular patch plasty with septal exclusion might be of value. Some patients with dilated cardiomyopathy and severe mitral regurgitation can benefit from a simplified mitral valvuloplasty.

Simple method for direct cannulation of ascending aortic aneurysms.

A simple method for direct cannulation of aneurysms of the ascending aorta is described. It avoids the need for femoral artery cannulation and offers an easy route for retrograde cerebral perfusion during deep hypothermic circulatory arrest.

The Maze operation for treatment of atrial fibrillation. Early clinical experience in a Scandinavian institution.

The Maze operation is a potentially curative surgical option in patients with disabling atrial fibrillation (AF) refractory to conventional treatment. The aim of this study was to evaluate the initial 4-year Maze experience in our institution. The study included 26 patients (19 males, mean age 55 years) who had undergone the Maze (III) operation between 1994 and 1998. Nine patients had surgery for concomitant heart disease. Follow-up was 3-55 (median 18) months. No deaths or neurological complications occurred; 22 patients are at present in regular sinus-, or junctional rhythm, 2 patients have permanent atrial pacing for symptomatic sinus node dysfunction, and 2 patients have had persistent AF, post surgery. Sinus node dysfunctions were detected in five patients, though not requiring pacemakers. Out of the total 26 patients, 23 are free of anti-arrhythmic drugs. Echocardiographic signs of left atrial contraction were recorded in 50% of the patients. The Maze operation offers a safe alternative to conventional therapy, with attractive results justifying expansion in the use of this treatment for AF.

Elimination of cholesterol as cholestenoic acid in human lung by sterol 27-hydroxylase: evidence that most of this steroid in the circulation is of pulmonary origin.

Human alveolar macrophages have exceptionally high capacity to convert cholesterol into 27-hydroxycholesterol and cholestenoic acid by the sterol 27-hydroxylase mechanism. It is shown here that the human lung has a higher content of 27-hydroxycholesterol relative to cholesterol than any other organ. In order to evaluate the importance of the sterol 27-hydroxylase mechanism for cholesterol homeostasis in the lung, the production of cholestenoic acid by human lung was investigated. Removal of one lung reduced the level of cholestenoic acid in the circulation by 48 +/- 4% (P < 0.005). The levels of cholestenoic acid in the pulmonary artery and in the pulmonary vein showed significant differences (P < 0.002) with higher levels in the pulmonary vein (108 +/- 16 and 104 +/- 16 ng/mL, respectively). This corresponds to a net flux of cholestenoic acid from the lung of about 14 mg/day, which is more than 80% of the reported removal of this oxysterol and its metabolites from the circulation by the liver per day. Bypassing the lung for 60 min led to a reduction in circulating cholestenoic acid (30%) that fits with a pulmonary origin when taking into account the half-life of cholestenoic acid. The level of circulating cholestenoic acid was found to be less in patients with different lung diseases. It is evident that most of the cholestenoic acid in the circulation is of pulmonary origin. The present results suggest that the sterol 27-hydroxylase in the lung is responsible for at least half of the total flux of 27-oxygenated cholesterol metabolites to the liver and that this enzyme system may be of importance for cholesterol homeostasis in the lung.

[A new surgical technique in atrial fibrillation. The maze procedure restores sinus rhythm]. / Ny hjärtkirurgisk metod vid förmaksflimmer. Maze-operation återställer sinusrytm.

Atrial fibrillation (AF) is a common arrhythmia associated with significant morbidity and increased mortality, partly due to the increased risk of stroke. The maze procedure, introduced by James Cox of the USA, is an internationally established surgical alternative in cases of unsuccessful medical or catheterised treatment of paroxysmal or chronic AF. It is an open heart procedure, involving multiple transmural incisions and continuous suture lines in both atria. By creating a maze of atrial tissue, the re-entrant circuits causing the AF are interrupted, hence re-establishing regular sinus rhythm and atrioventricular synchronization. The article reviews the initial 3-year experience of the procedure in 10 patients with AF, either paroxysmal (n = 5) or chronic (n = 5). The indications for surgery were disabling symptoms in all 10 cases, medical treatment failure in nine cases, previous AF-associated stroke in three cases, and a significant atrial septal defect in one case. All patients underwent extensive investigation both pre- and post-operatively. Postoperatively, nine of the 10 patients manifested regular sinus or atrial rhythm and freedom from or amelioration of preoperative symptoms associated with AF. There were no deaths, neurological complications or long-term recurrence of arrhythmia. One patient had an early recurrence of AF that was not amenable to medical treatment, and was subsequently treated with His' bundle ablation. Of the remaining nine patients, seven manifested signs of some postoperative atrial contraction at echocardiography, the occurrence of which needs to be borne in mind with a view to reducing the risk of future thromboembolic events. We recommend the maze procedure as an attractive surgical option in cases of unsuccessful medical treatment of paroxysmal or chronic AF.

Early autograft endocarditis after Ross operation: a case history.

A case of early autograft endocarditis occurring three weeks after a Ross operation is described. The origin of the infection appeared to be the proximal suture line of the autograft and the pathology included subvalvular destruction of the autograft, a pseudoaneurysm between the autograft and the left atrium, and a fistula to and a vegetation in the roof of the left atrium. The valve cusps were unaffected and there was only slight autograft insufficiency (grade I-II). The autograft was removed and successfully replaced with a homograft.

Postinfarction left ventricular pseudoaneurysm--echocardiographic diagnosis and surgical repair.

Left ventricular wall perforation after acute myocardial infarction, without immediate rupture to fatal haemopericardium, is a rare complication that may result in a pseudoaneurysm. Transoesophageal echocardiography demonstrated a posterior wall perforation and the unique blood flow pattern at the neck of a pseudoaneurysm 6 days after acute myocardial infarction. In a second patient with angina and congestive heart failure 7 years after an acute myocardial infarction echocardiography demonstrated a huge pseudoaneurysm. Surgical repair was successful in both patients. Turbulence of blood at the neck of a pseudoaneurysm generates a murmur, and systolic regurgitation into a large aneurysm may cause symptoms of heart failure. Exact diagnosis, anatomical relations and size can be assessed with echocardiography. Angiography is required before surgery only to rule out coronary artery pathology. Occasionally a pseudoaneurysm may persist for many years but because of a high risk of rupture, prophylactic repair is indicated soon after diagnosis.

Myocardial release of troponin T after coronary bypass surgery.

The temporal changes in cardiac S-troponin T, S-creatine kinase-MB(S-CK-MB)mass and S-myoglobin were studied for 5 days after coronary bypass grafting in 70 patients. Perioperative infarction occurred in ten patients (2 Q wave, 8 non-Q wave). All three markers showed significant increase even in patients without signs of perioperative infarction. Within 8-12 hours their levels rose significantly (p < 0.001) more in the infarction than in the non-infarction cases. Troponin T and CK-MBmass both showed early (< 8-12 h) peaks in patients with perioperative infarction. CK-MBmass returned to near normal levels within 48-72 hours, whereas troponin T remained markedly increased throughout the observation. Myoglobin concentrations varied widely among the infarction cases. In the non-infarction group, troponin T and CK-MBmass (but not myoglobin) were related to the aortic cross-clamp time. Troponin T (but not CK-MBmass) remained elevated throughout the study period in patients with longer cross-clamp times. These findings may indicate continuous release from damaged myocardium in cases of perioperative infarction. Troponin T and CK-MBmass can serve as markers of perioperative infarction and troponin T may also be useful as a marker in studies on myocardial protection.

Release of von Willebrand factor by cardiopulmonary bypass, but not by cardioplegia in open heart surgery.

von Willebrand Factor (vWF) is released from endothelial cells. Increased vWF in the coronary circulation during cardiac surgery could be a potential indicator of coronary endothelial injury or stimulation, and thus a possible tool to evaluate regimens of myocardial protection. Release of vWF was investigated in 12 patients undergoing coronary artery bypass surgery with cardiopulmonary bypass (CPB). Concomitant samples of arterial and coronary sinus blood for measurement of vWF (antigen method) were drawn before start of CPB and 1, 4, 10 and 30 min after release of the aortic cross clamp. Additional arterial samples were drawn pre-, per-, and postoperatively. Preoperative arterial vWF was 1.58 +/- 0.59 IU/ml (mean +/- SD), and increased during CPB (highest level 2.37 +/- 0.76 IU/ml, p < 0.0026). No difference between arterial and coronary sinus vWF levels was found. Arterial vWF increased further the first postoperative day (3.96 +/- 0.92 IU/ml, p < 0.0026). In conclusion, systemic vWF is increased during CPB, and may be a possible marker of endothelial injury/activation to evaluate deleterious effects of different equipment for CPB. Reperfusion of the ischaemic, cardioplegic heart did not release vWF in the coronary circulation.

Doppler-derived pressure differences in normally functioning aortic valve prostheses. Studies in Björk-Shiley monostrut and Biocor porcine prostheses.

To determine the normal range of maximum and mean Doppler-derived pressure differences for mechanical and bioprosthetic valves in the aortic position, Doppler echocardiography was performed on 239 stable patients with normally functioning Björk-Shiley monostrut (BSM, n = 185) or Biocor porcine (n = 54) prostheses. The interval from aortic valve replacement to echocardiography was 3-9 days. Maximum and mean pressure differences were significantly greater in 21 mm than in 25 or 27 mm BSM prostheses. The pressure differences in 23 mm BSM valves did not diverge significantly from those in 21, 25 or 27 mm valves. The mean pressure difference did not exceed 30 mm Hg in any type or size of studied prosthesis. No significant differences were found in pressure gradients in comparisons between BSM and Biocor prostheses of corresponding sizes. The calculated velocity ratio for BSM prostheses was not significantly influenced by the valve size. We suggest that the normal range of Doppler-derived maximum and mean pressure differences determined in this study be adopted as reference in evaluations of aortic BSM and Biocor valve prostheses.

Aortic valve replacement in octogenarians with aortic stenosis: a case-control study.

OBJECTIVES: This study was designed to compare the results of aortic valve replacement in patients greater than or equal to 80 years old with those in patients 65 to 75 years old. BACKGROUND: Aortic valve replacement may be potentially more complicated and require the use of more resources when performed in octogenarians rather than in younger patients. Few hard data on this possibility are available. METHODS: The study group comprises all 44 patients greater than or equal to 80 years old (mean age 82 years) who underwent aortic valve replacement at our institution between January 1981 and July 1989. A control group of 83 patients with a mean age of 70 years was matched with the study group for gender and approximate date of valve replacement. Before operation, 86% of the older patients versus 36% of the younger patients were in New York Heart Association functional class III or IV (p less than 0.001). Data were retrospectively collected from hospital records and a self-assessment telephone interview was conducted. RESULTS: The early mortality rate was 14% in the older group versus 4% in the younger group (p = 0.045). The duration of respirator support, intensive care and the total duration of the hospital stay did not differ significantly between groups. The incidence of postoperative low cardiac output syndrome was higher in the older group (p = 0.049), but the incidence of late valve-related complications was similar in the two groups. The 2-year survival rate (including data on patients who died early) was 73% in the older group and 90% in the younger group (p = NS). Six months postoperatively all patients but one were in functional class I or II. CONCLUSIONS: Although the patients greater than or equal to 80 years old had a poorer preoperative status than that of younger patients, aortic valve replacement in this group did not require more use of hospital resources and resulted in a clinical improvement comparable to that of younger patients.