Preserved cardiorespiratory function and NT-proBNP levels before and during exercise in patients with recent onset of rheumatoid arthritis: the clinical challenge of stratifying the patient cardiovascular risks.

Rheumatoid arthritis (RA) is associated with an increased risk of myocardial infarction and congestive heart failure. In RA patients, elevated NT-proBNP levels have been reported to be a prognostic marker of left ventricular dysfunction. In this study, we evaluated cardiorespiratory functional capacity and NT-proBNP levels before and during cardiopulmonary exercise test in early RA (ERA) patients. Twenty ERA patients and 10 healthy controls were studied by color Doppler echocardiography to evaluate ventricular systolic and diastolic function. Arterial stiffness and wave reflections were quantified non-invasively using applanation tonometry of the radial artery. Cardiopulmonary treadmill test was performed to measure peak VO2 and VE/VCO2 parameters. NT-proBNP plasma levels were measured before and at the exercise peak during cardiopulmonary exercise. The peak oxygen uptake [VO2 (ml/min/kg)], the ventilatory equivalents for carbon dioxide (EqCO2), respiratory exchange ratio and arterial stiffness were similar between patients and controls during cardiopulmonary exercise test. Basal and peak cardiopulmonary exercise NT-proBNP plasma levels were comparable in ERA patients with respect to healthy controls. When we analyzed patients according to disease characteristics and cardiovascular risk factors, ERA patients with high disease activity, BMI > 25 kg/m2 and ACPA positivity presented significantly higher baseline and exercise peak NT-proBNP levels. Cardiorespiratory function is preserved in patients with recent onset of rheumatoid arthritis. The increased basal and exercise peak NT-proBNP plasma levels in patients with negative disease prognostic factors represent a possible marker to stratify the cardiovascular risk in patients with early rheumatoid arthritis.

Prediction of functional capacity by low-dose dobutamine stress echocardiography in chronic heart failure.

AIM: The aim of this study was to determine if low-dose dobutamine stress echocardiography (LD-DSE) is associated with functional capacity in unselected elderly patients with chronic heart failure. METHODS: This was a prospective trial. Thirty five consecutive patients were included, with age >65 years and left ventricular dysfunction (12 ischemic), by blindly assessed LD-DSE and cardiopulmonary exercise testing (CPT). Contractile reserve was defined as a change (D) in wall motion score index (WMSI) = or <0.2 at peak dose dobutamine. At CPT treadmill exercise time, peak VO2, %Vo2 and VE/VCO2 slope were determined. Preserved functional capacity was defined as percent of maximal predicted O2 consumption (%VO2) >80%. Baseline NT-proBNP plasma levels were assessed. RESULTS: CPT variables were not related to clinical and baseline echocardiography characteristics but were related to DWMSI (exercise time, P=0.004; peak VO2, P=0.008; %VO2, P<0.001; VE/Vco2, P<0.001). Contractile reserve was present in 16 of 17 patients with preserved functional capacity (sensitivity=94%) and in 2 of 13 patients without (specificity=85%). Baseline NT-proBNP levels were lower in patients with contractile reserve (476+/-365 pg/mL) than in those without (1 345+/-1 219 pg/mL) (P=0.019), but were mildly related to CPT variables (P=0.049 and 0.027 with exercise time and %VO2, respectively). CONCLUSION: Contractile reserve elicited at LD-DSE is associated with functional capacity in unselected elderly patients with chronic heart failure.

Assessment of left ventricular systolic dysfunction by tissue Doppler imaging to detect subclinical cardiomyopathy early after anthracycline therapy.

AIM: Anthracycline (ANT) chemotherapy for breast cancer, while associated with high response rates, is fraught by risks of irreversible cardiotoxicity. Unfortunately means to detect such cardiotoxicity early on and at a sublinical stage are lacking. We evaluated the role of systolic tissue Doppler imaging (TDI) in appraising postchemotherapy left ventricular (LV) remodelling. METHODS: Patients undergoing ANT-chemotherapy for breast cancer were enrolled, and underwent baseline and >6-months echocardiography (standard and TDI). According to the pattern of LV-TDI systolic remodelling from baseline to follow-up, patients were stratified in: group 1 (no LV-TDI worsening), group 2 (minor LV-TDI worsening), and group 3 (major LV-TDI worsening). Fifty-six patients were included (follow-up 9+/-6 months). RESULTS: At baseline, no patient had abnormal LV ejection fraction (LVEF), LV-TDI systolic dysfunction or New York Heart Association (NYHA) >1. Follow-up overall analysis showed significant deterioration in LVEF, end-diastolic diameter (EDD) end-systolic diameter (ESD), and TDI-systolic parameters (all P<0.05). Specifically, 29 (51.8%) patients showed no adverse LV-TDI systolic remodelling, while 17 (30.4%) were in group 2, and 10 (17.9%) in group 3. All groups shared similar conditions at baseline. Patients with adverse LV-TDI remodelling had significant increases in EDD and ESD, as well as a significantly decreased LVEF (all P<0.05). No patient in group 1 had abnormal LVEF at follow-up, while 1 patient in group 2 and 2 patients in group 3 had abnormal LVEF (P<0.05). CONCLUSION: Subclinical systolic dysfunction occurs in almost 50% of patients early after chemotherapy for breast cancer, with a more adverse by LV-TDI remodelling implying a more pronounced deterioration of standard echocardiographic parameters.

[Cardiorespiratory fitness and arterial stiffness in sedentary and not sedentary hypertensive workers]. / Relazione tra VO2 e Augmentation Index in lavoratori sedentari e non, affetti da ipertensione arteriosa.

In hypertensive subjects, arterial stiffness and arterial wave early reflection are thought to be the major factor limiting cardiac reserve and exercise capacity. Aortic augmentation index (AIx) is a measure of arterial wave reflection and stiffness, and has been associated with decreased cardiorespiratory fitness. We investigated the role of physical activity at work and its effect on such association. 25 hypertensive middle-aged workers, without history of diabetes, cardiovascular disease, renal failure and inflammatory diseases, were studied. Our study confirms that AIx provides information for the prediction of VO2 peak, being also gained with a non-invasive and practical test. Inside the two groups of sedentary and non sedentary workers, the relation between AIx and VO2 peak is still significant; whereas the non sedentary group showed a worse cardiorespiratory fitness without significantly differences in arterial stiffness.

Dipyridamole stress echocardiography vs dipyridamole sestamibi scintigraphy for diagnosing coronary artery disease in left bundle-branch block.

STUDY OBJECTIVES: To evaluate dipyridamole stress echocardiography (DSE) for predicting coronary artery diseases (CADs) in patients with complete left bundle-branch block (LBBB). DESIGN: Comparison of DSE and dipyridamole sestamibi myocardial perfusion scintigraphy (sestamibi). SETTING: Tertiary-care cardiac referral center. PATIENTS: Fifty-four consecutive patients (26 men; mean [+/- SD] age, 59 +/- 7 years) with complete LBBB (14 patients with left ventricular [LV] dilatation) and intermediate probability of CAD. METHODS: Simultaneous single photon emission CT scan (20 mCi technetium Tc 99m stress/rest sestamibi) and echocardiography (second harmonic imaging) during a two-step (0.56 to 0.84 mg/kg) dipyridamole infusion protocol. Two sestamibi readings were performed. The first reading considered only those studies with reversible defects (sestamibi-1) to be positive. The second reading considered those studies with any defect (sestamibi-2) to be positive. CAD was defined as a >or= 50% reduction in diameter in at least one major vessel seen on coronary angiography. RESULTS: CAD was present in 17 patients (31.5%). The global predictive accuracy for CAD was significantly higher for DSE (87.0%) and sestamibi-1 (79.6%) than for sestamibi-2 (57.4%) [p < 0.01 vs DSE; p < 0.05 vs sestamibi-1]. No significant differences in sensitivity were present, but specificity was significantly higher for DSE (94.6%) and sestamibi-1 (81.1%) than for sestamibi-2 (43.2%; p < 0.01 vs both the other two tests). Of 14 patients with LV dilatation, 26.8% were falsely positive for CAD (in some cases for posterior defects) as determined by sestamibi-1 and 64.3% were falsely positive for CAD by sestamibi-2 vs none by DSE. CONCLUSIONS: DSE is at least as accurate as dipyridamole sestamibi scintigraphy for predicting CAD in patients with complete LBBB and tends to be more specific in those patients with underlying LV dilatation.

Myocardial contrast echocardiography: a new tool in the noninvasive assessment of perfusion.

Although the ability to visualize the microvascular circulation by injection of microbubbles has been recognized for over 30 years, only recently the considerable progress in both ultrasound techniques and new contrast media has made myocardial contrast echocardiography a reliable, noninvasive method for the assessment of regional myocardial perfusion. Several clinical studies have validated this technique for the identification of resting myocardial perfusion defects after myocardial infarction and the detection of no-reflow in ischemia-reperfusion model. In addition, preliminary studies have shown the ability of this method to recognize regional myocardial ischemia during pharmacological stress tests in known or suspected coronary artery disease. Finally, in the experimental setting, the estimation of different degrees of severity of coronary artery stenosis has been proposed using the quantitative assessment of myocardial perfusion by time-intensity curves. Although to date some unresolved questions hinder the routine clinical application of this novel noninvasive technique, myocardial contrast echocardiography is close to providing significant advances in the ultimate goal of any cardiac imaging technique, i.e. the simultaneous assessment of both perfusion and function.

Modulation of vascular endothelial gene expression by physical training in patients with chronic heart failure.

BACKGROUND: Abnormalities of the skeletal muscle vasculature, such as endothelial dysfunction and reduced microvascular density, can be reversed by physical training in patients with chronic heart failure. The molecular mechanisms that mediate the beneficial effects of physical training on the vascular endothelium are unknown. METHODS: Endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) gene expression in the skeletal muscle, peak oxygen consumption (VO2) and calf peak reactive hyperemia were measured before and after 12 weeks of supervised physical training in 10 patients with chronic heart failure. Five patients with heart failure of similar severity who did not participate in the training program served as controls. RESULTS: The effects of physical training on eNOS and VEGF gene expression were heterogeneous. eNOS gene expression increased 3-4 fold in 4 patients while it remained constant in 6 patients. VEGF gene expression increased significantly in all patients who were not treated with beta-adrenergic blockade and remained constant in all patients who were treated with beta-adrenergic blockade. In contrast, physical training increased peak VO2 and calf peak reactive hyperemia in all patients. Mean peak VO2 increased from 13.13 +/- 2.21 to 16.19 +/- 2.69 ml/kg/min (p < 0.001) and calf peak reactive hyperemia increased from 19.7 +/- 2.3 to 29.6 +/- 4.0 ml*min(-1)*100 ml(-1) (p < 0.001). CONCLUSIONS: A supervised program of physical training that consistently enhanced peak VO2 and vascular reactivity in patients with chronic heart failure increased or left eNOS and VEGF gene expression unchanged in skeletal muscle. Changes in vascular endothelial gene expression may contribute to the benefits of training on vascular endothelial function but are not solely responsible for these benefits.

Neuroadrenergic activation and response to dobutamine in congestive heart failure secondary to idiopathic dilated cardiomyopathy.

Detection of contractile reserve is important in heart failure patients. To determine if detection of contractile reserve is influenced by neuroadrenergic activation, we examined the relation between dobutamine stress echocardiography (DSE) findings and plasma norepinephrine levels (NE) at rest in 35 patients with nonischemic left ventricular (LV) dysfunction (New York Heart Association class >III in all; LV ejection fraction 0.27 +/- 0.5). Changes in global wall motion score (WMS), and separately in WMS of hypokinetic segments and akinetic segments, were analyzed. A patient was considered to be responsive to dobutamine if the change in global WMS was >/=4. Twenty-three patients were responsive and 12 were not responsive to dobutamine. Plasma NE and baseline heart rate were significantly higher in nonresponsive patients (p <0.001). Changes in global WMS and in hypokinetic segment WMS were inversely related to either plasma NE (r -0.68 and -0.67, respectively) or baseline heart rate (r -0.60 and -0.66, respectively). The change in akinetic segment WMS was related to plasma NE only (r -0.50). Changes in WMS were not related to age, diastolic and systolic LV volume, baseline global WMS, or number of akinetic segments at baseline. Plasma NE >602 pg/ml predicted a blunted or absent contractile reserve at DSE (sensitivity 92%; specificity 87%). Neuroadrenergic activation may influence contractile reserve found at DSE in patients with heart failure due to nonischemic LV dysfunction.

Central pulmonary artery lesions in chronic obstructive pulmonary disease: A transesophageal echocardiography study.

BACKGROUND: In patients with acute pulmonary embolism, transesophageal echocardiography (TEE) often reveals presumably thrombotic lesions within the central pulmonary arteries (CPAs). These CPA lesions, when found in patients with primary pulmonary hypertension, have been attributed to in situ thrombosis or atherosclerosis. We hypothesized that similar CPA lesions may also develop in patients with chronic obstructive pulmonary disease (COPD) in the absence of pulmonary embolism. METHODS AND RESULTS: We examined by TEE 25 patients with COPD and 27 control patients with left heart disease. None of the patients had previous pulmonary embolism or ileofemoral and popliteal vein thrombosis. By use of TEE, CPA lesions were found in 12 COPD patients (48%) and 2 control patients (7.4%) (P<0.01). When CPA lesions were subdivided into types 1 (protruding and mobile) and 2 (wall-adherent), type 1 lesions proved to be uncommon, being found within the pulmonary trunk in 12% and 3.7% of COPD and control patients, respectively (P=NS). Conversely, type 2 lesions, which were always localized in the right pulmonary artery, were frequent in COPD patients (36%) and rare in control patients (3.7%) (P<0.01). When available, helical CT and MR angiography confirmed TEE findings, supporting an atherosclerotic origin of type 2 lesions, which were different from typical thrombotic lesions. FEV(1)/FVC ratio, RV/TLC ratio, PaO(2), hematocrit value, and pulmonary artery systolic pressure were not significantly different in COPD patients with and without CPA lesions. At TEE, however, COPD patients with CPA lesions showed a larger size of the main and right pulmonary arteries. CONCLUSIONS: TEE often reveals CPA lesions in stable patients with COPD even in the absence of significant pulmonary hypertension and not in close relation with the severity of pulmonary dysfunction.

Echocardiographic imaging in coronary artery disease: new techniques.

When analyzing left ventricular wall motion and thickening, two-dimensional echocardiography (2DE) represents a useful non-invasive tool for diagnosing and stratifying ischemic heart disease. New important technical advancements, such as harmonic imaging, allow to overcome limitations due to poor echocardiographic image quality in a large proportion of patients. Combination of exercise or pharmacological stress test with on-line echo images monitoring expands 2DE diagnostic and prognostic value in both ischemia or viability assessment. Study of contrast agents distribution is very promising for clarifying the complex interaction between myocardial perfusion and functional correlates, including myocardial stunning, hibernation and no-reflow phenomena. Direct visualization of epicardial coronary arteries and assessment of coronary artery blood flow has recently been demonstrated to be possible by either transthoracic (TTE) or transesophageal echocardiography (TEE). Acoustic quantification (AQ), automatic border detection (ABD), tissue Doppler imaging (TDI), and color kinesis are other technical modalities which may result to be useful for clinical evaluation of patients with either acute or chronic coronary syndromes.

Risk stratification of patients undergoing peripheral vascular revascularization by combined resting and dipyridamole echocardiography.

Patients with advanced peripheral vascular disease have an increased cardiac morbidity and mortality. The aim of this study was to assess the predictive value of rest and stress echocardiography for perioperative and late cardiac events in 110 patients undergoing limb revascularization. All patients underwent preoperative clinical and echocardiographic evaluation at rest and by dipyridamole stress testing to assess cardiac risk. Patients with > or =3 clinical Eagle markers, low left ventricular ejection fraction at rest, or positive dipyridamole stress test results were considered at high cardiac risk. To record adverse cardiac events, all patients were monitored during and after surgery, and followed for at least 1 year after hospital discharge. Cardiac complications occurred in 10 patients (9.7%) perioperatively (2 fatal myocardial infarctions), and in 13 (13%) at 1-year follow-up (7 fatal myocardial infarctions). Echocardiographic evaluation was the best predictor of early (p <0.00003) and late (p <0.0003) cardiac complications. No patient with a negative dipyridamole stress test result and good left ventricular ejection fraction had cardiac complications, either postoperatively or during follow-up. Clinical evaluation does not appear sufficiently sensitive for predicting perioperative cardiac events, but was valuable in predicting late cardiac complications (p <0.0002). Our data show that echocardiographic evaluation of resting dysfunction and of the ischemic response to dipyridamole is a good predictor of perioperative cardiac risk, and is superior to generally available clinical data. Echocardiographic evaluation is useful in defining a low-risk group of patients who can safely undergo limb revascularization, whichever surgical procedure is proposed.

Safety of endovascular treatment in high-cardiac-risk patients with limb-threatening ischemia.

Vascular surgery can be safely performed in approximately 60% of patients with advanced peripheral vascular disease, because of the high frequency of concomitant coronary artery disease and consequent increased risk of perioperative cardiac complications. The aim of this study was to validate the hypothesis that endovascular revascularization could be safely applied to high-cardiac-risk patients with a lower incidence of perioperative cardiac complications. One hundred and fourteen patients with peripheral vascular disease referred for revascularization underwent preoperatively a clinical and echocardiographic evaluation, at rest and under dipyridamole stress test, to assess the cardiac risk. Patients with high clinical score (according to Goldman and Detsky), or low left ventricular ejection fraction at rest, or positive dipyridamole stress test, were considered at high cardiac risk. To record adverse cardiac events, all patients were monitored during surgery, postoperatively, and followed up for 18 months after hospital discharge. Forty-eight patients (42%) were found to be at high cardiac risk. In this high-cardiac-risk group, endovascular surgery was performed in 37/48 patients (77%) (group A), while the remaining 11/48 patients (23%) were bypassed with open surgery (group B). Postoperative cardiac complications occurred in 16% of patients in group A and in 45% of patients in group B with two deaths (p < 0.05). At follow-up, 51% of patients in group A and 44% of patients in group B had suffered late cardiac events (p=ns), with 10 deaths in group A and three deaths in group B (p=ns). Limb salvage rate was similar in the two groups (95% group A, 100% group B; p=ns). These data show that high-cardiac-risk patients with limb-threatening ischemia have significantly less perioperative cardiac complications when treated by endovascular procedures instead of bypass surgery. Follow-up data on cardiac events confirm the severity of concomitant coronary artery disease in patients with peripheral vascular disease.

Comparison of steerable continuous-wave versus pulsed-wave Doppler ultrasonography to renal artery angiography in diagnosing renal artery stenosis.

Pulsed-wave Doppler ultrasonography is widely used to noninvasively diagnose renal artery stenosis. The use of steerable continuous-wave Doppler has never been tested. We compared pulsed and steerable continuous-wave Doppler ultrasonography, demonstrating that although both methods are highly sensitive for severe stenoses, continuous-wave Doppler shows a better sensitivity for mild to moderate stenoses.

Contractile reserve of dysfunctional myocardium after revascularization: a dobutamine stress echocardiography study.

OBJECTIVES: We sought to investigate the effects of revascularization on the contractile reserve of dysfunctional myocardium. BACKGROUND: The improvement in dysfunctional but viable myocardium after revascularization is frequently less than expected from the amount of contractile reserve detected on dobutamine stress echocardiography. The fate of the contractile reserve, when it does not result in an adequate contractile recovery, is unknown. METHODS: Basal contraction and contractile reserve of infarct zones were assessed by dobutamine stress echocardiography in 21 postinfarction male patients before and > 3 months after revascularization (30 infarct zones; mean +/- SD left ventricular ejection fraction 35 +/- 8%). An infarct zone wall motion score index (WMSI) was calculated. RESULTS: Before revascularization, contractile reserve was present in 14 infarct zones (12 patients) and absent in 16 (9 patients). After revascularization, ejection fraction increased by 5 +/- 4% (p < 0.01) in patients classified as positive for contractile reserve and remained unchanged in those classified as negative. New York Heart Association classification improved in 58.3% and 22.2% of patients, respectively. Basal contraction improved in eight zones with previous contractile reserve (57.1%) and in one zone without (6.3%) (p < 0.01). Contractile reserve was still evident in 13 zones with previous contractile reserve (93%; 8 with contractile recovery), and it developed in 6 zones without (38%; none with contractile recovery). WMSI values after revascularization were decreased from values before revascularization during low dose dobutamine in zones with and without previous contractile reserve (p < 0.01 and < 0.05, respectively). CONCLUSIONS: After revascularization, contractile reserve is maintained or even increases in viable infarct zones that do not recover as expected. It may also develop in some infarct zones judged not to be viable before revascularization. This increased contractile reserve may play a role in the functional improvement of patients after revascularization.

Plasma beta-endorphin response to exercise in patients with congestive heart failure.

OBJECTIVE: To determine whether the net release of beta-endorphin during exercise, similar to that of norepinephrine, is related to functional disability in patients with congestive heart failure. BACKGROUND: Plasma beta-endorphin and norepinephrine levels are elevated at rest in patients with heart failure, reflecting a functional disability. The net release of beta-endorphin during exercise in patients with heart failure is unknown. METHODS: We measured plasma beta-endorphin and norepinephrine levels (respectively: radioimmune and radioenzymatic assay) at rest and during graded exercise testing in 28 patients with congestive heart failure (Weber's class A, 10; B, 9; and C, 9) and in 9 normal subjects. RESULTS: At rest, plasma beta-endorphin levels were higher in patients in classes B and C than in normal subjects (p < 0.05 and < 0.01, respectively). At peak exercise, patients in different functional classes and normal subjects reached similar beta-endorphin levels. However, the net release of beta-endorphin during exercise was lower in patients in classes B and C than in those in class A and normal subjects (p < 0.01 for both). At rest, plasma norepinephrine levels were significantly higher in patients than in normal subjects (p < 0.01). At peak exercise, norepinephrine levels were significantly lower in class C patients than in normal subjects (p < 0.05), and tended to be lower in patients in classes A and B (p = NS). The net release of norepinephrine during exercise was lower in patients than in normal subjects (p < 0.01). In patients, releases of both beta-endorphin and norepinephrine during exercise were related to peak oxygen consumption and duration of exercise, but not to resting left ventricular ejection fraction. CONCLUSIONS: In patients with congestive heart failure, the net release of plasma beta-endorphin during exercise is decreased, like norepinephrine, and reflects a functional disability.

Circulating levels of cytokines and their endogenous modulators in patients with mild to severe congestive heart failure due to coronary artery disease or hypertension.

OBJECTIVES: This study sought to determine the circulating levels of cytokines and their respective endogenous modulators in patients with congestive heart failure of variable severity. BACKGROUND: Activation of immune elements localized in the heart or periphery, or both, may promote release of cytokines in patients with congestive heart failure. Although an increased circulating level of tumor necrosis factor-alpha (TNF-alpha) and its soluble receptor type II (sTNF-RII) is well documented, less is known about other cytokines (i.e., interleukin-1-beta [IL-1-beta], interleukin-6 [IL-6] and interleukin-2 [IL-2] and their soluble receptor/receptor antagonists). METHODS: Circulating levels of TNF-alpha and sTNF-RII, IL-1-beta, IL-1 receptor antagonist (IL-1-Ra), IL-6, IL-6 soluble receptor (IL-6-sR), IL-2 and IL-2 soluble receptor-alpha were measured using enzyme-linked immunosorbent assay kits (Quantikine, R&D Systems) in 80 patients with congestive heart failure due to coronary artery disease or hypertension. The severity of their symptoms, which ranged from New York Heart Association functional class I to IV, was confirmed by measurement of peak oxygen consumption. RESULTS: The percentage of patients with elevated levels of cytokines and their corresponding soluble receptor/receptor antagonists significantly increased with functional class. For TNF-alpha and IL-1-beta, the percentage of patients with elevated levels of soluble receptor/receptor antagonists was higher than that of patients with elevated levels of the cytokine itself. For IL-6, the percentage of patients with elevated levels of IL-6-sR tended to be lower than that of patients with elevated levels of IL-6. All but two patients had undetectable levels of IL-2, and all but seven had levels of IL-2-sR within a normal range. CONCLUSIONS: In patients with congestive heart failure, circulating levels of cytokines increased with the severity of symptoms. In these patients, circulating levels of sTNF-RII and IL-1-Ra are more sensitive markers of immune activation than are circulating levels of TNF-alpha and IL-1-beta, respectively. Levels of IL-2 and IL-2-sR are not elevated when congestive heart failure is due to coronary artery disease or hypertension.

[Doppler flow-velocity analysis of the renal arteries in left ventricular dysfunction]. / Analisi della curva di flusso-velocità doppler delle arterie renali nella disfunzione ventricolare sinistra.

AIM OF THE STUDY: Chronic heart failure leads to renal hypoperfusion. Clinical methods for monitoring renal artery flow have several limitations. We analyzed the renal artery flow-velocity in patients with left ventricular dysfunction and normal controls by pulsed-wave (PW) color-guided Doppler technique. The relation between PW Doppler quantitative indexes and left ventricular ejection fraction (LVEF), creatinine clearance, and age, was also assessed. METHODS: We studied 53 patients with left ventricular dysfunction (LVEF by 2D echo < or = 40%) and no systemic hypertension, diabetes, parenchymal nephropathy, serum creatinine levels > 150 mmol/l, nor renal artery stenosis. Five patients were excluded for suboptimal renal artery PW Doppler recordings. Thus, the study group was constituted of 48 patients (mean age: 64 +/- 13 years). Twenty-eight normal subjects (mean age: 61 +/- 9 years) were the control group. By PW Doppler we measured the maximum (Vmax), the minimum (Vmin) and the mean (Vmean) velocities of both renal arteries. The resistivity index (RI), obtained from the formula (Vmax-Vmin)/ Vmax, and the pulsatility index (PI), obtained from the formula (Vmax-Vmin)/Vmed were calculated. Creatinine clearance was determined in each patient. RESULTS: RI and PI were greater in patients with left ventricular dysfunction than in normal controls. In normal controls, RI and PI were related to age (r: 0.63, p < 0.001; and r: 0.45, p < 0.05) and creatinine clearance (r: -0.44 and -0.40, respectively; both: p < 0.05), not to LVEF. In patients with left ventricular dysfunction, RI and PI were related to LVEF (r: -0.67 and -0.59; both: p < 0.001), other than to age (r: 0.57 and 0.55; both: p < 0.001) and creatinine clearance (r: -0.59, p < 0.001, and r = -0.46, p < 0.01, respectively). In this group, however, there was no sharp separation of RI and PI between patients with different degree of left ventricular dysfunction (LVEF < or = 30% and > 30%). CONCLUSIONS: In patients with left ventricular dysfunction, by renal artery PW Doppler analysis it is possible to detect noninvasively a reduction in regional flow-velocity and an increase in Doppler-derived vascular resistance indexes. These Doppler changes mainly depend on severity of left ventricular dysfunction and less on age of patients.

Regional wall motion analysis by dobutamine stess echocardiography to distinguish between ischemic and nonischemic dilated cardiomyopathy.

To distinguish between ischemic and nonischemic dilated cardiomyopathy (DCM), we studied 43 patients with left ventricular dysfunction (15 ischemic and 28 nonischemic detected by coronary angiography) by dobutamine stress echocardiography. At rest, there were more normal segments (p<0.001) and a trend toward more akinetic segments (p, not significant) per ischemic than per nonischemic DCM patient. However, either at rest or with low-dose dobutamine, individual data largely overlapped. At peak dose, in ischemic DCM, regional contraction worsened in many normal or dys-synergic regions at rest (in the latter case after improvement with low-dose dobutamine); in contrast, in nonischemic DCM, further mild improvement was observed in a variable number of left ventricular areas. Thus with peak-dose dobutamine, more akinetic and less normal segments were present per ischemic than per nonischemic DCM patient (both, p<0.001). A value of six or more akinetic segments was 80% sensitive and 96% specific for ischemic DCM. Our data show that analysis of regional contraction by dobutamine stress echocardiography can distinguish between ischemic and nonischemic DCM.

Significance of transient ST-T segment changes during dobutamine testing in Q wave myocardial infarction.

OBJECTIVES: We evaluated dobutamine stress electrocardiography for detecting potentially reversible contractile dysfunction or residual ischemia in the infarct-related area. BACKGROUND: ST-T segment changes in pathologic Q wave leads during stress testing may reflect contractile reserve, inducible ischemia or passive mechanical stretching. Dobutamine echocardiography allows detection of contractile reserve at low doses and inducible ischemia at high doses. METHODS: We used low (5 to 10 microg/kg body weight per min) and high doses (20 to 40 microg/kg per min) of dobutamine in 49 patients with a previous Q wave myocardial infarction and analyzed the relation between ST-T segment changes in pathologic Q wave leads and regional contraction. RESULTS: At low dose dobutamine, regional contraction improved in the infarct-related area in 23 patients. New or further ST segment elevation and pseudonormalization of negative T waves developed at low doses more frequently in patients with than without contractile reserve (both p < 0.001), giving a sensitivity of 43.5% and 60.9% and a specificity of 100% and 96.2%, respectively. At high dose dobutamine (43 patients), new or further ST segment elevation and pseudonormalization of negative T waves, occurring beyond those observed at low doses, had a low predictive accuracy for contractile reserve (sensitivity of 9.5% and 14.3% and specificity of 68.2% and 81.8%, respectively). Pseudonormalization of negative T waves at high dose dobutamine was 100% specific (but only 25% sensitive) for homozonal ischemia. CONCLUSIONS: ST segment elevation or pseudonormalization of negative T waves, or both, is indicative of contractile reserve in the infarct-related area when either develops at low dose dobutamine, but may be associated with worsening or no change in contractile function at high doses.