Kari S Virtanen

Helsinki University Central Hospital | HUCH · Cardiovascular Laboratory (retired)

Objectives: This study sought to report the 5-year follow-up results of the Nordic Bifurcation Study. Background: Randomized clinical trials with short-term follow-up have indicated that coronary bifurcation lesions may be optimally treated using the optional side branch stenting strategy. Methods: A total of 413 patients with a coronary bifur...

We sought to evaluate the prognostic impact of age on the procedural results and subsequent clinical outcomes in patients with multivessel disease (MVD) treated either by coronary artery bypass surgery (CABG) or by percutaneous coronary intervention (PCI) with or without drug eluting stents, based on data of the Arterial Revascularisation Therapies...

Background: Renal insufficiency has been correlated with less favorable outcomes following revascularization by either coronary artery bypass surgery (CABG) or percutaneous coronary intervention (PCI) in patients with ischemic heart disease, but few studies have compared outcomes in these patients according to the method of revascularization.

Large individual variability in clopidogrel responses has been reported. However, mechanisms of the non-responsiveness are unclear. Our aim was to study the extent of platelet inhibition at the receptor level by in vitro receptor antagonists of P2Y(12) (AR-C69931MX, cangrelor) and P2Y(1) (adenosine 3',5'diphosphate) in aspirin treated patients with...

The risk of stent thrombosis has been reported to increase with percutaneous coronary intervention (PCI) complexity. The present study reports the pre-specified secondary endpoint of a 14-month stent thrombosis and major adverse cardiac events in patients stented with a simple versus a complex bifurcation technique using sirolimus eluting stents (S...

Myocardial gene and cellular therapies have revived the use of porcine ischemic heart models. Commonly applied ameroid-obstruction produces inconsistent coronary stenoses and myocardial lesions, whereas abrupt coronary occlusion causes arrhythmias and sudden death. To produce a constant myocardial lesion after adaptation to ischemia, we surgically...

The optimal stenting strategy in coronary artery bifurcation lesions is unknown. In the present study, a strategy of stenting both the main vessel and the side branch (MV+SB) was compared with a strategy of stenting the main vessel only, with optional stenting of the side branch (MV), with sirolimus-eluting stents. A total of 413 patients with a bi...

Besides being a known lymphangiogenic activator, vascular endothelial growth factor (VEGF)-C may express angiogenic potential by proteolytic cleavage and activation of endothelial cells. We assessed myocardial collateral formation and functional changes after adenovirus-mediated VEGF-C gene transfer in an ischemic porcine model. Fifteen Landrace pi...

Our aim was to evaluate the early efficacy and variability of the platelet inhibition exerted by 300 mg clopidogrel for the purpose of acute percutaneous coronary interventions using platelet function tests. Elective percutaneous coronary intervention was used as a timely model in which clopidogrel was added to ongoing acetylsalicylic acid (aspirin...

Transmyocardial laser revascularization (TMLR) creates channels in the myocardium. The aim of the treatment is to relieve angina in patients with end-stage coronary artery disease. We studied the effect of TMLR on myocardial function and perfusion with the combination of cine magnetic resonance imaging (MRI) and thallium scintigraphy. Eight patient...

Body surface potential mapping is superior to 12-lead electrocardiogram in detection of acute and old myocardial infarctions. We examined the capability of the ST-T integral and T wave to detect exercise-induced ischemia in body surface potential mapping. Body surface potential mapping with 123 channels was recorded in 70 subjects: 45 coronary arte...

Reversible or irreversible myocardial damage due to ischemia correlates with altered membrane functions of the cells. To compare myocardial free fatty acid (FFA) metabolism and flow during exercise induced ischemia we studied ten patients with coronary artery disease but without previous myocardial infarction. A series of post-exercise single-photo...

Background Atherosclerosis is the most common complication of diabetes. Correction of hyperglycaemia helps to prevent microvascular complications but has little effect on macrovascular disease. Post-hoc analyses of diabetic subpopulations in lipid intervention trials suggest that correction of lipoprotein abnormalities will lead to a decrease in co...

New-onset atrial fibrillation (AF) is frequent after coronary artery bypass grafting (CABG), and beta-blockers decrease its incidence. To examine whether a beta-blocker with class III properties is superior to a pure one, 191 consecutive patients undergoing CABG were randomized to receive oral sotalol, 120 mg daily (n = 93), or metoprolol, 75 mg da...

Background and Aim: We studied the acute and chronic effects of 2 years of LDL apheresis (Liposorber™ LA-15 system) on cholesterol metabolism in 7 subjects with familial hypercholesterolemia (one homozygote and 6 heterozygotes) with concomitant statin and resin treatment in order to determine the long-term metabolic consequences when cholesterol sy...

Our purpose was to use multislice MRI for detection of reversible myocardial ischemia and assessment of the effect of revascularization on tissue perfusion in patients with coronary artery disease. Eleven patients with single-vessel proximal left anterior descending coronary artery disease were studied with MRI and thallium scintigraphy before and...

Twenty of 569 consecutive patients (3.5%) undergoing percutaneous transluminal coronary angioplasty required emergency coronary artery bypass grafting for acute closure of the dilated vessel. In seven patients an intracoronary autoperfusion balloon catheter was inserted to ensure antegrade blood flow across the injured zone of the coronary artery....

Cardiotoxicity is a potential adverse effect of anthracycline (A) therapy. Radiotherapy (XRT) may also cause a variety of cardiac complications. The purpose of the present study was to evaluate these cardiac side-effects in children and adolescents treated for cancer. We assessed the cardiac status of 91 patients, divided into three groups: Group A...

Abnormalities in HDL and an increased risk of coronary artery disease (CAD) coexist in non-insulin-dependent diabetes mellitus (NIDDM). HDLs can be separated by their apolipoprotein (apo) content into particles containing apoA-I but not apoA-II (LpA-I) and those containing both apoA-I and apoA-II (LpA-I:A-II). The LpA-I particles have been suggeste...

The aim of the study was to evaluate the cardiopulmonary exercise tolerance in children and adolescents after chest irradiation and anticancer chemotherapy. We studied 30 subjectively asymptomatic patients aged 8 to 25 years treated for pediatric malignancies with chest irradiation (XRT) +/- chemotherapy. The median interval since XRT was 7 (range,...

High density lipoprotein (HDL) subfractions (2b, 2a, 3a, 3b, and 3c) separated by gradient gel electrophoresis (GGE) and defined by Gaussian summation analysis, and the compositions of HDL2 and HDL3, separated by preparative ultracentrifugation, were studied in four groups of men with or without non-insulin-dependent diabetes mellitus (NIDDM) and c...

Of 41 pediatric patients currently alive after total body irradiation (TBI) and bone marrow transplantation (BMT), 30 (allogeneic 20, autologous 10) participated in the study. Pre-transplant therapy included high-dose cyclophosphamide (CY) and TBI (n = 12), high-dose CY alone (n = 4), high-dose Ara C and TBI (n = 5), cisplatinum, high-dose melphala...

In many patients with valvular aortic stenosis (AS), management decisions may be possible without invasive studies if coexistent coronary artery disease (CAD) can be ruled out noninvasively. The use of thallium-201 single-photon emission computed tomography to the exclusion of CAD was studied in 44 patients aged 41 to 78 years with AS. In addition...

In two groups of patients, coronary artery bypass surgery for angina pectoris included internal mammary artery (IMA) sequential grafts (group I) or single grafts (group II). At postoperative angiography all grafts were patent. In addition, the patients received on average 1.8 vein grafts into other coronary arteries. The mean interval to postoperat...

The occurrence and influence of coronary collateral circulation and obstruction of the supplying coronary arteries on left ventricular contractility, prevalence of myocardial infarction, and bicycle exercise ergometer test were studied in a random sample of 286 patients with angiographically documented coronary artery disease. Collaterals appeared...

The occurrence and influence of coronary collateral circulation and obstruction of the supplying coronary arteries on left ventricular contractility, prevalence of myocardial infarction, and bicycle exercise ergometer test were studied in a random sample of 286 patients with angiographically documented coronary artery disease. Collaterals appeared...

Seventy-one coronary artery bypass grafting (CABG) reoperations were performed during a 17-year period, comprising 2.7% of all CABG operations. The main indication (in 87%) was vein graft failure alone or combined with other causes. Progression of disease in native coronary arteries was the sole indication in only 4 of the 71 cases. There were seve...

Between November 1987 and April 1988, the right gastroepiploic artery (GEA) was used as a coronary artery bypass graft in 11 patients, 9 men and 2 women. In 1 of them, the GEA was used because no veins were available; in the others, the GEA was used to avoid the use of vein grafts. The GEA was anastomosed to the right coronary artery in all patient...

We have assessed the angiographic features of a group of 37 patients given oral dipyridamole and 37 patients given matching placebo. Both groups represented severe coronary arterial disease and were studied prior to bypass surgery. Six patients (16%) had angina and 13 patients (35%) had electrocardiographic changes after dipyridamole. All the patie...

Seventy-one patients undergoing reoperation for coronary artery disease were examined on average 2.5 years postoperatively. Operative mortality was 9.9% and late mortality 6.3%. 88% of the patients improved subjectively, and although only 7.8% were angina-free, 79.9% were in NYHA Class I or II. All patients who had been working before reoperation r...

The results of exercise electrocardiography were studied in a random sample of 317 subjects with clinical suspicion of coronary artery disease. In 278 patients with coronary artery disease the rate of false negative tests was 18% with and 12% without previous myocardial infarction. If ST elevation was considered a negative response, the correspondi...

Ergometer exercise electrocardiographic (EECG) data were surveyed in a series of 328 patients (277 men and 51 women) subjected to coronary arteriography. The sensitivity and specificity of EECG for coronary artery disease (CAD) were 84% and 54%, respectively. The predictive accuracy of a positive test for CAD was 95% in men and 81% in women. The pr...

During the years 1977 to 1983, 1,458 pacemakers were implanted or reimplanted in our clinic. Seventy-nine patients were treated during the same period for pacemaker system infections. The time interval between the preceding surgical maneuver and the manifest infection was 11.9 +/- 10.2 months in the catheter fistulas and 12.2 +/- 11.5 months in the...

Large coronary artery aneurysms may interfere with coronary flow, cause compression, and/or may rupture. Circulatory shock from thrombosis and rupture of an aneurysm of the right coronary artery in a patient is reported here. This formation, 7 cm in diameter, was visible by computed tomogram but the diagnosis was revealed only during surgery. The s...

Patients with chest pain syndromes and normal coronary angiograms were studied with a new set of methods that included thermodilution coronary sinus blood flow and coronary dye dilution curves with special computer analysis, oxygen and lactate determinations, thallium scannings, atrial pacing and dipyridamole tests. The following observations and c...

The sudden jamming of a prosthetic valve disc is one cause for postoperative hemodynamic deterioration. This complication occurred in 10 instances (2% of disc valves implanted), resulting in 4 fatalities. In 6 patients the disc entrapment was a complication following mitral valve replacement, and in 4 others the malfunction followed aortic valve su...

This paper reports a case of severe low output cardiac failure due to congestive (alcoholic) cardiomyopathy which was unresponsive to dopamine infusion, but which improved rapidly on intravenous practolol therapy. The therapeutic range of beta-blockade turned out to be quite narrow.

Simultaneous assessment of coronary flow and flow-volume relation makes it possible to evaluate the dilatatory responses of coronary vasculature. Anew set up of methods for investigation of the coronary circulation was employed to study the nature of the coronary flow and volume responses to dipyridamole in dogs. The turnover rate of coronary blood...

Incidence of microbial colonization related to medical devices was prospectively studied in 101 consecutive patients treated in intensive care unit ICU. Following endotracheal intubation 50% of patients had positive bacterial culture in the trachea within 24 hours irrespective of the use of antibiotics. Positive urine cultures occurred in 33% of pa...

A triad of exertional chest discomfort, transient rate-dependent left bundle branch block (LBBB), and normal coronary arteries is presented in seven consecutive patients. Although the clinical symptoms resembled effort angina, qualities atypical of classic angina pectoris were commonly noted: 1) the onset was always abrupt; and 2) the pain was loca...

The effects of metropolol (beta 1-selective), propranolol (nonselective) and clonidine (central alpha-stimulant) on plasma norepinephrine, blood pressure and heart rate were assessed at rest, during isometric work and dynamic exercise in 15 patients with moderate hypertension. Metroprolol resulted in a lower diastolic blood pressure during isometri...

Devices available for isometric handgrip testing revealed constructional deficiences likely to give rise to inaccurate data. A new electrical device was constructed which eliminates the defects in earlier designs. The new equipment consists of a U-shaped handgrip transducer, a measuring device, and a slave monitor for the patients. The patient's ma...

Four patients with total occlusion of the left main coronary artery are described. Angina pectoris was severe (NYHA class 3-4) and had lasted 20 months to seven years. Three patients had experienced a myocardial infarction. All displayed large collaterals arising from a nearly normal right coronary artery and feeding both the left anterior descendi...

Using I131-albumin labelling of plasma and a special biopsy cutting device, the blood content of the subendocardium and subepicardium was determined in guinea pig hearts. Measurements were done both in untreated animals and after intravenous administration of metoprolol, a new cardioselective beta-blocking compound. The data were compared with resu...

Das sogenannte Subkommissuralorgan, welches sich aus Ependymzellen am Anfang des Aquaeductus cerebri aufbaut, zeigt sekretorische Elemente. Es handelt sich dabei um Mucopolysaccharide. Diese sind vergleichbar dem neurosekretorischen Material im Hinterlappen der Hypophyse. Diese Massen lassen sich durch eine Fuchsinfrbung darstellen. Mnnlichen Ratte...

Total heart block appeared in a middle-aged male patient during an attack of gout. Total block changed into Wenckebach phenomenon three days after the beginning of uricosuric treatment. On the fourth day only first-grade A-V block was left. The improvement of conductivity corresponded well to the lowering of the serum uric acid concentration and th...