Myocardial perfusion in patients with typical chest pain and normal angiogram.

BACKGROUND: Approximately 10-30% of patients with typical chest pain present normal epicardial coronaries. In a proportion of these patients, angina is attributed to microvascular dysfunction. Previous studies investigating whether angina is the result of abnormal resting or stress perfusion are controversial but limited by varying inclusion criteria. Therefore, we investigated whether microvascular dysfunction in these patients is associated with perfusion abnormalities at rest or at stress. PATIENTS AND METHODS: In 58 patients (39 female, 19 male, mean age 58+/-10 years) with angina and normal angiogram as well as 10 control patients with atypical chest pain and normal coronaries (six female, four male, mean age 53+/-11 years) myocardial blood flow (MBF) was measured at rest and under dipyridamole using 13N-ammonia PET. Resting MBF and coronary flow reserve (CFR) as the ratio of hyperaemic to resting MBF were corrected for rate-pressure-product (RPP): normalized resting MBF (MBFn)=MBFx10,000/RPP and CFRn=CFRxRPP/10,000. RESULTS: Sixteen/58 patients had a normal CFRn (=2.5; group I; CFRn: 3.1+/-0.88); the same as the controls (CFRn: 3.3+/-0.74). Forty-two/58 patients presented a reduced CFRn (group II; CFRn: 1.78+/-0.57). Group II had both a higher MBFn (group II: 1.30+/-0.33 vs. Group I: 1.03+/-0.26; P<0.05 and vs. controls: 1.07+/-0.19; P<0.01) and a lower hyperaemic MBF (group II: 2.25+/-0.76 mL g-1 min-1 vs. Group I: 3.07+/-0.78 mL g-1 min-1; P<0.001 and vs. controls: 3.41+/-0.94 mL g-1 min-1; P<0.0001). CONCLUSION: Impaired CFRn in patients with typical angina and normal angiogram is owing to both an increased resting and reduced hyperaemic MBF. Therefore, PET represents a prerequisite for further studies to optimize treatment in individuals with anginal pain and normal coronary angiogram.

[Left ventricular dysfunction in Churg-Strauss syndrome]. / Linksventrikuläre Dysfunktion im Rahmen von Churg-Strauss-Syndrom.

Churg-Strauss syndrome is a rare disorder characterized by hypereosinophilia and a systemic vasculitis occurring inpatients with asthma and allergic rhinitis. Vasculitis commonly affects the lungs, the heart, the skin, and the peripheral nervous system. Cardiac involvement is characterized by acute and constrictive pericarditis, myocarditis and endocarditis, as well as ischemic cardiomyopathy. Endomyocardial fibrosis similar to Loeffler's syndrome has been rarely described. In the presented case, a 43 year old man with a history of allergy and asthma suffered from increasing dyspnea, fever, pulmonary infiltates and cardiomyopathy. Laboratory studies were notable for marked hypereosinophilia. In a bronchoscopic lavage and transbronchial biopsy eosinophilic infiltrates accompanied by vasculitis were found, Churg-Strauss syndrome was diagnosed. Echocardiogram showed endomyocardial deposits in the apex of the right ventricle, right ventricular function was normal particular in the basal segments. The left ventricle was slightly enlarged and left ventricular function was impaired. The diastolic mitral in-flow showed a restrictive pattern. Additionally, a pericardial effusion was observed without signs of tamponade. The patient received corticosteroids, cyclophosphamide and cardiomyopathy-specific therapy and showed a marked improvement after 4 months.

Endocarditis by Lactobacillus rhamnosus due to yogurt ingestion?

A young man who ate large quantities of probiotic yogurt developed endocarditis and septic arthritis caused by Lactobacillus rhamnosus. The pathogenic isolate could not be distinguished from the yogurt microflora using methods routinely used in the clinical microbiology laboratory. Only by using more appropriate methodology, including PCR, the pathogen could be distinguished from the yogurt isolate.

[Ductus arteriosus apertus as the cause of recurrent nerve paralysis. A case report]. / Der Ductus arteriosus apertus als Ursache einer Parese des N. recurrens. Ein Fallbericht.

There are various reasons for paralysis of the vocal folds, which consequently imposes great demands on differential diagnostics. Angiocardiopathies are regarded as very rare cases of etiopathogenesis. In the present case, a persistent arterial duct could be identified as the reason for the paralysis of the left recurrent nerve of a 59-year-old female patient. The necessity of interdisciplinary diagnostics going beyond the field of otorhinolaryngology is emphasized, especially in cases of a paralysis of the recurrent nerve.

Limitations of the transpulmonary indicator dilution method for assessment of preload changes in critically ill patients with reduced left ventricular function.

OBJECTIVE: We examined whether intrathoracic blood volume (ITBV) and total end-diastolic volume (TEDV), determined by the transpulmonary indicator dilution technique, adequately reflect preload changes during fluid administration in patients with reduced left ventricular function. DESIGN: A prospective, controlled, clinical study. SETTING: Medical intensive care unit in a university hospital. PATIENTS: A total of 18 sedated, mechanically ventilated, and moderately hypovolemic intensive care unit patients, eight with reduced left ventricular function (ejection fraction area, 24.9+/-8.0%, group A), ten with normal left ventricular function (ejection fraction area, 57.6+/-13.0%, group B). INTERVENTIONS: Continuous crystalloid infusion over 120 mins at a constant rate of 8 mL/kg/30 mins. MEASUREMENTS AND MAIN RESULTS: Stroke volume index, central venous pressure, pulmonary artery occlusion pressure (PAOP), TEDV, and ITBV were determined simultaneously at baseline and serially every 30 mins during continuous crystalloid infusion. A similar series of measurements was obtained during control conditions. Performance of various variables during fluid administration was assessed by time correlation analysis. Sensitivity for various variables defined as the ability to detect increasing amounts of administered fluid in individual patients was calculated. All examined variables increased during fluid administration and were unaffected during the control period. Mean time correlation (r2) was significantly higher for pressure monitoring (central venous pressure, r2 = 0.8281; PAOP, r2 = 0.5476) than for volume variables (TEDV, r2 = 0.0256; ITBV, r2 = 0.0729) in group A and was high for all variables in group B (central venous pressure, r2 = 0.7056; PAOP, r2 = 0.6241; TEDV, r2 = 0.49; ITBV, r2 = 0.4225). Sensitivities for central venous pressure, PAOP, TEDV, and ITBV after 120 min were 63%, 75%, 25%, and 25% in group A and 90%, 100%, 60%, and 60% in group B, respectively. CONCLUSION: This study demonstrates limitations of the transpulmonary indicator dilution technique for monitoring of intravascular volume in patients with reduced left ventricular function.

Stimulating effect of biologically modified low density lipoproteins on ADP-induced aggregation of washed platelets persists in absence of specific binding.

Oxidized low density lipoproteins are closely associated with atherosclerosis and also might be directly involved in thrombosis because they have been shown to mediate a stimulating effect on human platelets. In this work, we used biologically modified low density lipoproteins (i.e., low density lipoproteins sufficiently oxidized to show specificity for the macrophage scavenger receptor system) to examine if specific binding of the oxidized apolipoprotein moiety to the platelet surface is a prerequisite for the platelet-stimulating effects reported by other authors. We find that biologically modified low density lipoproteins show specific binding to human platelets (K(d)=5.83+/-0.4 microg/mL, 3850+/-620 sites/platelet) and strongly augment both ADP- and thrombin-induced aggregation of washed platelets. Maleylated albumin, an antagonist of oxidized low density lipoproteins binding to all currently classified scavenger receptors, is able to reduce platelet oxidized low density lipoproteins binding to background levels. Nevertheless, maleylated albumin is not able to exert any kind of normalizing effect on the augmented ADP-induced aggregation response observed in the presence of biologically modified low density lipoproteins. From these data, we conclude that specific binding of oxidatively modified apolipoprotein B to the platelet surface is not essential to the process of platelet stimulation. Therefore, we conclude that these stimulating effects may be mediated by unidentified compounds formed in the lipid phase of the lipoproteins.

Effects of vitamin E on chronic and acute endothelial dysfunction in smokers.

OBJECTIVES: The aims of this study were to determine whether chronic or acute impairment of flow mediated vasodilation (FMD) in the brachial artery of smokers can be restored or preserved by the antioxidant vitamin E. BACKGROUND: Transient impairment of endothelial function after heavy cigarette smoking and chronic endothelial dysfunction in smokers result at least in part from increased oxidative stress. METHODS: We studied 22 healthy male smokers (mean +/- SD, 23 +/- 9 cigarettes per day) randomly assigned to receive either 600 IU vitamin E per day (n = 11, age 28 +/- 6 years) or placebo (n = 11, age 27 +/- 6 years) for four weeks and 11 age-matched healthy male nonsmokers. Flow mediated vasodilation and endothelium-independent, nitroglycerin-induced dilation were assessed in the brachial artery using high resolution ultrasound (7.5 MHz) at baseline and after therapy. Subjects stopped smoking 2 h before the ultrasound examinations. At the end of the treatment period, a third scan was obtained 20 min after smoking a cigarette (0.6 mg nicotine, 7 mg tar) to estimate transient impairment of FMD. RESULTS: Flow mediated vasodilation at baseline was abnormal in the vitamin E (5.3 +/- 3.8, p < 0.01) and in the placebo group (6.4 +/- 3.5, p < 0.05) compared with nonsmoking controls (11.6 +/- 4.7). Using a two-way repeated measures analysis of variance (ANOVA) to examine the effects of vitamin E on FMD, we found no effect for the grouping factor (p = 0.5834) in the ANOVA over time but a highly significant difference with respect to time (p = 0.0065). The interaction of the time factor and the grouping factor also proved to be significant (p = 0.0318). Flow mediated vasodilation values remained similar after treatment for four weeks in both groups but declined faster after smoking a cigarette in subjects taking placebo compared with those receiving vitamin E (p values from successive differences for the time/group factor: 0.0001/0.0017). The transient attenuation of FMD (calculated as the percent change in FMD) was related to the improvement of the antioxidant status, estimated as percent changes in thiobarbituric acid-reactive substances (r = -0.67, p = 0.0024). Nitroglycerin-induced dilation did not differ between study groups at baseline or after therapy. CONCLUSIONS: These results demonstrate that oral supplementation of vitamin E can attenuate transient impairment of endothelial function after heavy smoking due to an improvement of the oxidative status but cannot restore chronic endothelial dysfunction within four weeks in healthy male smokers.

Aerobic capacity in adult dermatomyositis/polymyositis patients and healthy controls.

OBJECTIVE: Assessment of myositis patients has relied on symptoms, strength testing, and serum muscle enzyme activity. Recently, functional assessments and evaluation of strength by dynamometry and of disease activity by magnetic resonance imaging have also been added. Aerobic testing in selected patients has been considered useful. DESIGN: Case-control study. SETTING: University Hospital, Vienna, Austria. PATIENTS: Twenty-two subjects (8 outpatients with chronic dermatomyositis and 3 outpatients with chronic polymyositis, and 11 healthy controls) participated, allowing the identification of 11 case-control pairs matched by age (+/-3 years) and gender (mean age, 48+/-14 yrs; ratio of women to men, 18/4). MAIN OUTCOME MEASURES: Target parameters were peak oxygen uptake (peak VO2) to estimate aerobic exercise capacity and peak isometric torque for muscle strength. Creatine phosphokinase (CPK) was measured to assess elevation of muscle enzymes. RESULTS: The mean peak VO2 in patients with dermatomyositis/polymyositis was 15.3 mL/min/kg (SD = 5.8) and in the healthy controls 28.7 mL/min/kg (SD = 7.8). Cardiorespiratory capacity expressed as peak VO2 was thus significantly reduced at 53% (p = .0001) of the control value. Muscle strength expressed as peak isometric torque was significantly lower (p = .01) in patients (mean 148+/-73 Nm) when compared to the control group (mean 261+/-99 Nm). In myositis patients peak VO2 and peak isometric torque correlate well with each other (r = .7631; p = .0001), but not at all with serum CPK levels (r = .056; p = .869). CONCLUSION: Peak VO2 is significantly diminished in patients with dermatomyositis/polymyositis, compared with age- and sex-matched controls. Serum CPK did not significantly correlate with VO2. Aerobic exercise testing may be a useful assessment parameter in selected patients with dermatomyositis/ polymyositis.

Functional assessment of coronary arteries by poststenotic intravascular Doppler ultrasound.

This study sought to delineate the impact of the rate pressure product on intraluminal Doppler velocity measurements and to determine the relation between poststenotic vasodilator reserve and percent luminal obstruction in coronary vessels. Twenty patients with single-vessel coronary disease were studied prior to coronary angioplasty and at follow-up 6 months later. Intracoronary velocity reserve after administration of adenosine was measured distal to the stenosis with a Doppler-tipped guide wire and was compared to quantitative coronary angiography and adenosine myocardial perfusion scintigraphy. The rate pressure product was confirmed as significant covariate (ANCOVA, p < 0.005) of intracoronary Doppler reserve. When normalized to rate pressure product, poststenotic Doppler velocity reserve in stenosed arteries was significantly lower than in patent arteries as classified by quantitative coronary angiography (1.7 +/- 0.6 vs. 2.9 +/- 0.5, p < 0.001) and perfusion scintigraphy (1.5 +/- 0.4 vs. 2.8 +/- 0.5, p < 0.001). Normalized Doppler velocity reserve showed a nonlinear but highly significant relation to percent area stenosis [y = 3.0.(1 - exp[0.081 (x - 100)]), p < 0.001]. When normalized Doppler velocity reserve was less than 2.0, coronary disease was identified with 95% specificity and 94% sensitivity in comparison to perfusion scintigraphy. Thus, in coronary arteries poststenotic Doppler reserve and percent area stenosis show a significant nonlinear relation. Doppler velocity reserve when normalized to rate pressure product can be used to characterize the hemodynamic impact of coronary obstructions.

Plasmin activation system in restenosis: role in pathogenesis and clinical prediction?

During recent years it has become increasingly recognized that the plasmin activation system is involved in the development of atherosclerosis and restenosis. Responsible pathophysiologic mechanisms, however, remain elusive. This review focuses primarily on the clinicians, point of view, suggesting that increases in plasminogen activator inhibitor type-1 (PAI-1) plasma levels after balloon angioplasty or permanently elevated lipoprotein (a) (Lp(a)) plasma levels might be helpful in the prediction of restenosis after coronary angioplasty. In contrast, tissue-type plasminogen activator (tPA) plasma levels appear unrelated to restenosis, and data regarding a possible role of urokinase-type plasminogen activator (uPA) in circulation are not available at present. Furthermore, a new hypothesis on the pathophysiological role of local PAI-1 overexpression as a beneficial negative feedback mechanism to limit excess cellular proliferation in atherogenesis and restenosis is presented.

Additional benefit of vitamin E supplementation to simvastatin therapy on vasoreactivity of the brachial artery of hypercholesterolemic men.

OBJECTIVES: The aim of this study was to determine whether the combination of lipid-lowering therapy and vitamin E supplementation improves peripheral endothelial function and whether it is more effective than lipid-lowering therapy alone. BACKGROUND: Endothelium-dependent vasodilation is impaired in coronary and peripheral arteries of patients with hypercholesterolemia. Coronary endothelial function has been shown to improve under lipid-lowering and antioxidant therapy, but the effect of additive vitamin E supplementation in the brachial artery is unknown. METHODS: Seven patients with hypercholesterolemia (mean+/-SD; age 51+/-10 yr) were studied. Endothelium-dependent, flow-mediated dilation (FMD) and endothelium-independent nitroglycerin-induced dilation (NMD) were assessed in the brachial artery using high resolution ultrasound 1) at baseline (BL I), 2) after 8 weeks of simvastatin (20 mg) and vitamin E (300 IU) therapy (Comb I), 3) after withdrawal of vitamin E for 4 weeks (Statin), 4) after therapy as in #2 for 4 weeks (Comb II) and 5) after withdrawal of both drugs for 4 weeks (BL II). RESULTS: Combined simvastatin and vitamin E therapy reduced total cholesterol (Comb I vs. BL I: 276+/-22 vs. 190+/-14 mg/dl, p < 0.0001) and low-density lipoprotein (LDL)-C (197+/-22 vs. 106+/-22 mg/dl, p < 0.00001), augmented alpha tocopherol levels normalized to LDL (12.2+/-4.1 vs. 4.9+/-0.9 microg alpha-T/100 mg% LDL-C, p < 0.01) and resulted in significant improvements in FMD (16.4+/-4.7 vs. 4.9+/-2.5%, p < 0.001) as well as NMD (17.9+/-4.3 vs. 11.2+/-2.8%, p < 0.01). The ratio of FMD to NMD (0.92+/-0.17 vs. 0.46+/-0.24%, p < 0.05) also increased under combination therapy, indicating a greater improvement of FMD than that of NMD. After withdrawal of vitamin E, both FMD (Comb I vs. Statin: 16.4+/-4.7 vs. 7.9+/-4.7%, p < 0.01) and NMD (17.9+/-4.3 vs. 10.9+/-4.5%, p < 0.05) decreased significantly such that simvastatin alone only tended to improve FMD and did not change NMD. Results under combination therapy (Comb II vs. BL II) were reproducible. CONCLUSIONS: Combined vitamin E and simvastatin therapy leads to an improvement of FMD and NMD in the brachial artery of patients with hypercholesterolemia. The improvement of FMD is more pronounced after combination therapy than after lipid-lowering therapy alone, similar to previous findings in the coronary circulation.

Comparison of transesophageal Doppler coronary flow reserve measurements with thallium-201 single-photon emission computed tomography imaging in assessment of left anterior descending artery stenoses.

BACKGROUND AND HYPOTHESIS: Recent studies demonstrate the feasibility of coronary flow reserve measurements by transesophageal echocardiographic (TEE) Doppler recordings of coronary sinus or left anterior descending (LAD) coronary artery flow velocity for detecting stenoses of the LAD artery. This study compares coronary flow reserve measurements by Doppler TEE with thallium-201 (201Tl) single-photon emission computed tomography (SPECT) in patients with proximal single-vessel LAD stenosis. METHODS: Nineteen patients with various degrees of LAD stenosis (mean area stenosis 71 +/- 24%; range 24-96%) were studied. Area stenosis by quantitative coronary angiography was < 75% in 7 patients and > 75% in 12 patients. Transesophageal LAD and coronary sinus Doppler measurements were performed at baseline and after intravenous dipyridamole. Coronary flow reserve was calculated as the ratio of hyperemic to baseline average peak velocities. Predefined coronary flow reserve cut-off values of 1.8 for the coronary sinus method and of 2.0 for the LAD method were used for diagnosis of significant LAD stenosis. Results were compared with qualitative 201Tl dipyridamole SPECT. RESULTS: Overall predictive accuracy for diagnosis of > 75% LAD stenosis was 79% for 201Tl SPECT, 77% for the transesophageal LAD and 79% for the transesophageal coronary sinus technique. Concordant results between 201Tl SPECT and the LAD and coronary sinus Doppler methods were observed in 79% and 71% of patients, respectively. CONCLUSIONS: Thallium-201 SPECT and transesophageal Doppler assessment of coronary flow reserve have similar accuracy for diagnosing significant proximal LAD stenosis. Therefore, both transesophageal Doppler techniques might constitute another widely available, noninvasive method for assessment of left coronary artery disease, if disease location is proximal.

Effect of antihypertensive treatment with doxazosin on insulin sensitivity and fibrinolytic parameters.

The effects of the selective alpha-1-adrenoceptor antagonist doxazosin on metabolic and fibrinolytic parameters were studied in hypertensive patients with various degrees of fasting plasma insulin levels (Group A: 22.5 +/- 3 microU/ml, Group B: 8.1 +/- 1.5 microU/ml; p <0.01) to disclose a potential link between a doxazosin-induced alteration of insulin and/or lipid metabolism and possible changes of these parameters on the fibrinolytic system. Doxazosin treatment resulted in a dose-dependent reduction of basal insulin levels in group A to 16 +/- 3 microU/ml; p <0.05. This finding was paralleled by a dose-dependent increase in t-PAmass concentration in the same patient group (basal t-PAmass from 9.7 +/- 1 to 15.5 +/- 2 ng/ml; p <0.05). As PAI-1 "active" as well as total antigen levels were not altered in parallel, the net effect on the endogenous fibrinolytic system is an increase of the fibrinolytic potential.

Relation of hemodynamic variables to augmentation of left anterior descending coronary flow by intraaortic balloon pulsation in coronary artery disease.

Recent studies suggest prophylactic intraaortic balloon-pulsation (IABP) in patients undergoing coronary reperfusion therapy. However, variable effects of IABP on coronary blood flow are reported. It is suggested that augmentation of coronary flow is more effective in patients with a compromised hemodynamic status, which might have potential relevance in selecting IABP treatment in patients undergoing reperfusion therapy.

Adverse cardiovascular effects of ketamine infusion in patients with catecholamine-dependent heart failure.

The longterm effects of ketamine on haemodynamic parameters and exogenous catecholamine requirements were studied in twenty-five critically ill patients with catecholamine-dependent heart failure. Following sedation with midazolam (0.15 +/- 0.07, mg.kg-1.h-1) and sufentanil (0.88 +/- 0.33 microgram.kg-1.h-1), patients with impaired left ventricular function (left ventricular ejection fraction area 30 +/- 7%) were randomly assigned to receive ketamine (2.5 +/- 0.9 mg.kg-1.h-1) and midazolam (Group A) or remained on sufentanil/midazolam (Group B). Haemodynamic measurements were performed throughout the first 24 hours after randomization. In group A cardiac index decreased by 21% (P = 0.01), mean arterial pressure increased by 13% (P = 0.01), mean pulmonary artery pressure by 14% (P = 0.04), pulmonary capillary wedge pressure by 20% (P = 0.03), and systemic vascular resistance index by 38% (P < 0.001). No significant cardiovascular effects were observed in Group B. Neither group had significant changes of exogenous catecholamine requirement. In conclusion, ketamine exhibits potential negative cardiovascular effects in patients with catecholamine-dependent heart failure. Therefore, ketamine should not be considered a first line drug for longterm sedation of patients with impaired left ventricular function.

Emergency aortic valve replacement for critical aortic stenosis. A lifesaving treatment for patients with cardiogenic shock and multiple organ failure.

OBJECTIVE: To demonstrate that emergency aortic valve replacement can be successfully performed in patients with critical aortic stenosis and reduced left ventricular function even in cardiogenic shock with associated severe multiple organ failure. DESIGN: Retrospective, consecutive case series. SETTING: Multidisciplinary intensive care unit of a tertiary care university hospital. PATIENTS: Five patients admitted to the intensive care unit with critical aortic stenosis (aortic valve area 0.56 +/- 0.13 cm2) and greatly reduced left ventricular ejection fraction (20 +/- 3%) in prolonged cardiogenic shock and associated multiple organ failure (Multiple organ failure score 6.8 +/- 0.5; Acute Physiology, Age, and Chronic Health Evaluation III score 91 +/- 27). INTERVENTION: Emergency aortic valve replacement. RESULTS: All patients survived with full recovery of organ function. At follow-up (18 +/- 10 months) all patients were in New York Heart Association functional class I or II with improvement of left ventricular ejection fraction to 48 +/- 25%. CONCLUSIONS: This excellent outcome suggests that emergency aortic valve replacement should be strongly considered in patients with critical aortic stenosis even in cardiogenic shock and multiple organ failure.

Comparison of transesophageal coronary sinus and left anterior descending coronary artery Doppler measurements for the assessment of coronary flow reserve.

BACKGROUND: Currently used methods for assessment of coronary flow reserve are invasive and require extensive laboratory equipment. Recently, noninvasive assessment of coronary flow reserve by transesophageal Doppler evaluation of coronary sinus (CS) or left anterior descending coronary artery (LAD) flow has been proposed. Direct comparison between these two techniques is lacking. METHODS: Doppler recordings of CS and LAD flow velocity were obtained before and after 0.6 mg/kg/5 min dipyridamole in 16 patients with significant stenosis of the LAD (Group A) and in 14 control patients (Group B). Flow recordings and all measurements were performed in a blinded manner. For assessment of coronary flow reserve, Doppler measurements after dipyridamole were divided by the respective baseline values. RESULTS: Doppler studies of the CS and LAD were feasible in 30 of 30 (100%) and 23 of 30 (71%) patients, respectively. Analyzing the maximum flow velocities, coronary flow reserve in Groups A and B was 1.18 +/- 0.28 and 1.68 +/- 0.53 with CS recordings and 1.78 +/- 0.83 and 2.51 +/- 0.76 with LAD recordings, respectively. Analyzing the velocity time integrals, coronary flow reserve in Groups A and B was 1.53 +/- 0.68 and 2.59 +/- 0.74 with CS recordings and 1.77 +/- 0.38 and 2.68 +/- 0.93 with LAD recordings, respectively. Correlation between LAD and CS recordings was 0.69 (p < 0.001), when coronary flow reserve was calculated from the velocity time integral and 0.68 (p < 0.001) when the maximum flow velocities were used. CONCLUSION: Both transesophageal Doppler techniques might be useful for noninvasive assessment of coronary flow reserve.

Transesophageal versus intracoronary Doppler measurements for calculation of coronary flow reserve.

OBJECTIVE: The present study was performed to compare coronary flow reserve by transesophageal Doppler echocardiography and intracoronary Doppler flow wire measurements in patients with LAD disease. METHODS: 17 patients with various degree of LAD stenosis were studied. Intracoronary LAD Doppler measurements were performed at baseline and after intracoronary injection of 18 micrograms adenosine. Transesophageal coronary sinus and LAD Doppler measurements were performed at baseline and after intravenous dipyridamole (0.6 mg/kg/5 min). Coronary flow reserve was calculated as the ratio of hyperemic to baseline average peak velocities. RESULTS: Coronary flow reserve was 2.44 +/- 0.62 and 2.19 +/- 0.76 for proximal and distal intracoronary measurements and was 2.25 +/- 0.64 and 1.74 +/- 0.63 for transesophageal LAD- and coronary sinus measurements. Proximal intracoronary flow reserve significantly correlated with transesophageal coronary sinus (r = 0.73, p < or = 0.001) and LAD (r = 0.70, p < or = 0.005) measurements, whereas distal intracoronary flow reserve only correlated with transesophageal coronary sinus flow reserve (r = 0.56, p < or = 0.02). Receiver operating characteristic curve analysis demonstrated similar diagnostic accuracy of all applied techniques for detection of a significant LAD stenosis. CONCLUSIONS: Coronary flow reserve by both transesophageal techniques correlated with intracoronary Doppler flow wire measurements, however considerable discrepancies may occur in the individual patient.

Effects of antihypertensive therapy on glucose and lipid metabolism.

Large epidemiological studies demonstrate only moderate reduction in the incidence of coronary artery disease by antihypertensive drug treatment. This is attributed to the prevalence of multiple risk factors in hypertensive patients and to possible adverse metabolic effects of antihypertensive drugs which may counteract their ability to reduce the risk of cardiovascular disease. The choices for pharmacological blood pressure reduction are divided between five classes with similar antihypertensive efficacy but markedly different influence on coronary risk factors. Hence, the clinician has to consider the prevalence of coexisting coronary risk factors, comorbidity as well as the efficacy, side effects, and mechanisms of drug action.