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Data concerning the effect of arterial compliance (AC) on hemodynamics during intraaortic balloon counterpulsation (IABC) are lacking. This study examines the effect of AC on acute hemodynamics induced by IABC in 15 patients with post-infarction cardiogenic shock. AC was estimated by aortic pulse wave analysis using the reflection time index (RTI). Measurements were obtained once per day during IABC. The % reduction in systolic aortic pressure (ASAP), end-diastolic aortic pressure (AEDAP) and the peak aortic diastolic augmentation (PADA) were used as performance indices of IABC; 107 sets of measurements were obtained. Multivariate analysis indicated an independent association of each IABC performance index with AC (p<0.05). A high AC group (RTI< or =20.6%, n=40) and a low AC group (RTI>20.6%, n=67) were obtained. DeltaSAP deltaEDAP and PADA were significantly higher in the low AC group by almost 75%, 54.6% and 11.3% (p<0.03), while arterial blood pressure did not significantly differ. Arterial compliance is an independent factor affecting hemodynamics during IABC. RTI values higher than 20.6% may predict a better acute hemodynamic response to IABC.

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The purpose of the present study was to evaluate the relation of the systemic arterial pulse pressure and other parameters derived from the 24-h arterial blood pressure (BP) monitoring to the severity of coronary artery disease, carotid lesions, and left ventricular (LV) mass index in patients without arterial hypertension. One hundred ten patients with known coronary artery disease underwent coronary arteriography, 24-h arterial BP monitoring, and ultrasound imaging of the carotid arteries and the myocardium. Measurements of 24-h arterial BP monitoring (systolic, diastolic, and average BP, pulse pressure, abnormal values of systolic and diastolic BP, and heart rate), the severity of coronary heart disease (Gensini score), intima-media thickness (IMT) of the common carotid artery and LV mass index were determined in all patients. By univariate analysis, only 24-h pulse pressure was significantly related to the severity of coronary artery disease (P < .01), carotid IMT(P < .01), and LV mass index (P < .01). In a multivariate analysis, 24-h pulse pressure was also the best predictor of the severity of coronary lesions (P = .009), carotid IMT (P = .003), and LV mass index (P = .009). Gensini score was related (P < .01) to LV mass index and not to carotid IMT. In conclusion, systemic arterial pulse pressure derived from 24-h arterial BP monitoring is related to coronary artery disease, carotid IMT, and LV mass index independently of age or any other derivative of 24-h arterial BP monitoring, indicating that this parameter could be a marker of global cardiovascular risk.

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BACKGROUND: The effect on infarct size of a pre-infarction high-grade, fixed coronary arterial stenosis maintained during reperfusion, was evaluated. METHODS: This experimental study was carried out in the research laboratory of a University Hospital. A canine occlusion-reperfusion model was used. Twenty-eight dogs underwent proximal left anterior descending (LAD) coronary artery occlusion (O). In Group 1 (n=6) the O lasted for 6 hours. In Group 2 (n=6) the O lasted for 2 hours followed by 4 hours of reperfusion (R). In Group 3 (n=3), LAD was stenosed for 30 minutes followed by O for 6 hours. In Group 4 (n=7) LAD was stenosed for 30 minutes followed by O for 2 hours and then 4 hours of R during which the artery was kept stenosed at the same degree (fixed) as the initial one. In Group 5 (n=6) the protocol was identical to Group 4 with the additional use of the intra-aortic balloon pump during R. RESULTS: The infarcted myocardium was almost the same in Groups 1 and 3 (80.0+/-10.6% vs 77.3+/-3.8%, respectively, p=NS), but less in Group 2 (59.0+/-19.9%, p=0.046 vs Group 1). There were no hemodynamic differences between Groups 4 and 5 and the infarcted myocardium was almost identical in both groups (37.7+/-18.8% and 38.7+/-19.1%, respectively, p=NS). The combined results of Groups 4 and 5, regarding the infarcted myocardium, was 38.1+/-18% (p=0.037 vs Group 2). CONCLUSIONS: In this acute coronary occlusion model, a pre-existing high-grade stenosis that maintained during reperfusion increased the amount of salvaged ischemic myocardium.

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STUDY OBJECTIVE: To evaluate the effects of long-term intermittent dobutamine infusion (IDI) with concomitant administration of low-dose amiodarone in patients with congestive heart failure (CHF) refractory to standard medical treatment. DESIGN: Prospective, interventional clinical trial. SETTING: Inpatient and outpatient heart failure clinic in a university teaching hospital. PATIENTS AND INTERVENTIONS: Twenty-two patients with CHF refractory to standard treatment who could be weaned from dobutamine therapy after an initial 72-h infusion were included in this study. The first 11 patients (group 1) were treated with IDI, 10 micromin, as needed (mean, once every 16 days, lasting for 12 to 48 h); the next 11 patients (group 2) received oral amiodarone, 400 mg/d, and IDI, 10 microg/kg/min, for 8 h every 7 days. MEASUREMENT AND RESULTS: There were no differences in baseline clinical, hemodynamic, and five biochemical characteristics between the two groups. The left ventricular ejection fraction was 13.5 +/- 4.5% in group 1 vs 15.5 +/- 4.9% in group 2 (mean +/- SD; p = 0.451); mean pulmonary capillary wedge pressure was 31.3 +/- 4.4 mm Hg vs 29.4 +/- 3.3 mm Hg (p = 0.316); serum creatinine was 1.9 +/- 0.4 mg/dL vs 1.6 +/- 0.5 mg/dL (p = 0.19); and serum Na was 139.6 +/- 6.2 mEq/L vs 138.4 +/- 3.1 mEq/L (p = 0.569). At 12 months of follow-up, 1 of 11 patients (9%) was alive in group 1 vs 6 of 11 patients (55%) in group 2 (p = 0.011). Furthermore, in group 2, the functional status improved significantly within the first 3 months of treatment, from New York Heart Association functional class IV to 2.63 +/- 0.5 (p = 0.0001). CONCLUSION: Long-term IDI in conjunction with amiodarone, added to conventional drugs, improved clinical status and survival of patients with severe CHF.

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BACKGROUND: Data on the reproducibility of serial measurements of ambulatory blood pressure in hypertensive patients are lacking. The purpose of this study was to examine (1) the reproducibility of four consecutive ambulatory blood pressure measurements, and (2) the reproducibility of nocturnal falls in blood pressure in hypertensive patients. METHODS: Twenty patients with mild to moderate essential hypertension underwent four separate ambulatory blood pressure monitorings, on the same day of the week, at 30-day intervals. Antihypertensive therapy was discontinued for 2 weeks before each recording. Comparing the mean values of blood pressure over 24h, as well as diurnal, nocturnal and hourly periods, among the four recordings determined the reproducibility of blood pressure measurements. A day/night difference in mean systolic and in mean diastolic blood pressure defined the nocturnal fall in blood pressure. RESULTS: No significant differences were observed in either hourly, 24-h, diurnal or nocturnal systolic blood pressure, diastolic blood pressure and heart rate, or in the nocturnal fall in systolic and diastolic blood pressure among the four recordings. CONCLUSIONS: Hourly systolic blood pressure, diastolic blood pressure, heart rate, and nocturnal fall in blood pressure were reproducible in four ambulatory blood pressure monitorings recorded over 4 months. These findings suggest that ambulatory blood pressure monitoring is a reliable tool to monitor blood pressure changes.

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Since 1988, we have been using double-disk devices with several device generations and improving results. Our current disk device, "The ButtonSeal Centering on Demand Device," is a multipurpose device made of stainless steel and polyurethane. It has shown high occlusion rates and no significant complications in atrial septal defects (ASDs) up to 30 mm in diameter. It can be used according to the ASD anatomy both in large, single defects (centering) and in multiple fenestrations (noncentering). The ButtonSeal shares the same limitations as other disk devices, namely, the possibility of wire-related problems and the need for significant septal rim. The development of wireless balloon-delivered devices and patches addresses these problems and limitations. Both detachable balloon devices and patches were used experimentally in animals and in feasibility studies in humans. The results showed good occlusion rates and lack of wire-related complications. Both methods required a minimal rim and occluded more defects than the disk devices. The transcatheter patch method was safer and had only one disadvantage, which was the need for 48-hour balloon support.

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Detachable balloon devices were applied in the occlusion of experimental ASDs in 20 piglets. The detachable balloons were made from Latex; the occluder balloon was placed on the left atrial side and required a floppy disk and counter-occluder(s) support from the right atrial side (17 experiments), or a second detachable balloon from the right side (3 experiments). Full occlusion was noticed in all cases. There was one device embolization in the descending aorta (device with a regular floppy disk and no counter-occluder). The device was covered by tissue in 3 to 4 weeks with the balloon flat on the septum in approximately 2 months; it required minimal rim and no wires in the left atrium. The double balloon model was wireless. The balloon detachable device was found effective and safe in the occlusion of experimental ASDs in piglets.

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OBJECTIVES: We sought to prospectively and randomly compare survival with clinical and hemodynamic variables in patients with congestive heart failure (CHF) treated with standard versus high doses of enalapril. BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors produce hemodynamic and symptomatic benefits in patients with CHF, but there is still controversy about the optimal dose in this clinical setting. METHODS: Two hundred and forty-eight patients with advanced CHF (age 56.3+/-12 years) were randomized to receive a maximal tolerated dose of enalapril, up to 20 mg/day in group 1 (mean dose achieved 17.9+/-4.3 mg/day, n = 122) and 60 mg/day in group 2 (mean dose achieved 42+/-19.3 mg/day, n = 126). RESULTS: At enrollment, patients in group 1 were in New York Heart Association (NYHA) functional class 2.6+/-0.7 and had a mean systolic blood pressure (SBP) of 117+/-18 mm Hg, a mean heart rate (HR) of 85+/-16 beats/min and a left ventricular ejection fraction (LVEF) of 20.0+/-9.8%. In group 2, patients were in NYHA class 2.6+/-0.7; their SBP was 118+/-17 mm Hg, HR 83+/-15 beats/min and LVEF 18.8+/-8.1%. There were no significant differences in these characteristics between the two groups of patients at enrollment. After 12 months of follow-up, 22 (18%) of 122 patients in group 1 and 23 (18%) of 126 patients in group 2 had died (p = 0.995, with 80% power of the study to detect a delta difference of 13%). The NYHA class was the same (1.9+/-0.7) in both groups; SBP was 111+/-16 and 111+/-17 mm Hg, HR 77+/-12 and 79+/-13 beats/min and LVEF 31+/-19% and 30+/-12% in groups 1 and 2, respectively. These differences were not statistically significant. The study had a power of 80% to detect (p = 0.05) the following changes: 13% in death rate, 0.25 units in NYHA class, 6 mm Hg in SBP, 5 beats/min in HR and 6% in LVEF. CONCLUSIONS: No significant differences were found in survival and clinical and hemodynamic variables between patients receiving standard and those receiving high doses of enalapril.

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This study examined the usefulness of 01 and QRS dispersion in the prognosis of patients with advanced congestive heart failure (CHF). One hundred four patients in New York Heart Association functional classes II to IV, with a left ventricular ejection fraction of <35%, and untreated with antiarrhythmic drugs, were followed prospectively. QRS and QT dispersion were defined as the maximum difference in QRS and QT interval duration, respectively, measured on all leads of standard 12-lead electrocardiograms. The end points of the study were non-sudden and sudden cardiac mortality. During an average follow-up of 20 months, there were 13 non-sudden and 10 sudden deaths. The average QRS duration was significantly longer in nonsurvivors than in survivors (125 ¿ 34 vs 113 ¿ 34 ms, respectively, p <0.04). Similar results were obtained with 01 dispersion (95 ¿ 48 ms vs 78 ¿ 31 ms, respectively, p <0.03) and QRS dispersion (54 ¿ 17 ms vs 46 16 ms, respectively, p <0.02). Furthermore, patients who died suddenly had significantly greater QRS dispersion than patients who survived (56 ¿ 13 vs 46 ¿ 16 ms, respectively, p <0.02). In a multivariate analysis, QT and QRS dispersion were both independent predictors of non-sudden cardiac death (p = 0.01 and p = 0.001, respectively), and QRS dispersion was also an independent predictor of sudden cardiac death (p = 0.04). Death rate in patients with 01 dispersion >90 ms was 2.8-fold higher than those with 01 dispersion 90 ms (95% confidence intervals [CI] 1.2 to 6.4). Similarly, the death rate in patients with QRS dispersion >46 ms was 3.9-fold higher than in those with QRS dispersion 46 ms (95% Cl 1.6 to 9.5). These findings suggest that QT and QRS dispersion are useful predictors of mortality in patients with advanced CHF. ¿2000 by Excerpta Medica, Inc.

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OBJECTIVE: A new derivative of 24 h ambulatory blood pressure monitoring (ABPM) is introduced and its association with left ventricular mass index (LVMI) in essential hypertension is examined. PATIENT: population One hundred and fifty-three previously untreated essential hypertension patients. METHODS: Patients underwent casual blood pressure (BP) readings, 24 h ABPM and left ventricular echocardiographic assessment The following 24 h awake and sleep ABP variables were calculated: mean systolic and diastolic BP, systolic and diastolic BP loads (percentage of systolic readings > 140/120 mmHg (day/ night) and diastolic readings > 90/80 mmHg (day/night)), standard deviation of systolic and diastolic ABP and nocturnal fall of systolic BP, as well as the integrated areas under the ABP curve. The area under the BP curve divided in horizontal slices was accurately modelled by a sigmoid curve. The parameters controlling the shape of the curve and in particular that regarding its 'slope' is hereafter called the 'pressure-time index'. RESULTS: 'Systolic pressure-time index 24 h' (SPTI24) is related to left ventricular mass index (multivariate analysis, P= 0.008). Using either partial correlation coefficients or a multivariate analysis, SPTI24 is related to left ventricular mass index, independently of age, casual blood pressure, mean systolic and diastolic ABP, systolic and diastolic BP loads, BP variability (standard deviation (SD), nocturnal fall of systolic BP) and integrated area under the curve (multivariate analysis, P= 0.004). CONCLUSIONS: In essential hypertension, the SPTI24 is related to LVMI independently of age, casual blood pressure, integrated area under the curve or any other derivative of 24 h ABPM, and might be used to assess the extent of hypertensive load.

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OBJECTIVE: To examine the effects of mechanical ventilation with positive end-expiratory pressure (PEEP), in conjunction with the intra-aortic balloon pump (IABP), on the outcome of patients in profound cardiogenic shock. PATIENTS: Twenty-eight consecutive patients presenting with myocardial infarction complicated by cardiogenic shock refractory to medical therapy, including dobutamine, dopamine and fluid administration. Eighteen patients were assisted by the IABP alone (IABP group), and ten patients by the IABP plus controlled mechanical ventilation with PEEP set at 10 cmH(2)O (IABP + CMV group). RESULTS: Weaning from mechanical assistance was accomplished in 8 out of 18 patients in the IABP group versus 9 out of 10 patients in the IABP + CMV group (p = 0.04). Ultimately, 5 of 18 patients in the IABP group were discharged from the hospital versus 8 of 10 patients in the IABP + CMV group (p = 0. 01). CONCLUSION: Mechanical ventilation with PEEP at 10 cmH(2)O supplements the IABP and may improve the survival rates of patients suffering from cardiogenic shock.

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This study examines the common carotid intimal-medial wall thickness (CCA-IMT) in untreated patients with elevated clinic blood pressure (BP) but normal ambulatory BP (isolated clinic hypertension, n = 22), in comparison with a group with elevated clinic and ambulatory BP (hypertensives, n = 41) and a group with normal clinic and ambulatory BP (normotensives, n = 17) readings. The three groups did not differ in age, male/female ratio, lipid profile, glucose tolerance test, or smoking habits. No difference existed in CCA-IMT values between the groups with hypertension (0.67 +/- 0.18 mm) and isolated clinic hypertension (0.68 +/- 0.14 mm), but the values in these two groups were significantly higher (one-way ANOVA; F = 8.09, P < .001) than in the group of normotensives (0.50 +/- 0.09 mm). The CCA-IMT did not correlate with clinic systolic or diastolic BP readings or with BP derivatives of 24-h ambulatory monitoring. Mean 24-h BP in the isolated clinic hypertensives did not differ from that in the normotensives, whereas both were lower than in the hypertensives. We conclude that changes in the CCA-IMT occuring in subjects with isolated clinic hypertension are equal to the changes in sustained hypertension, indicating that isolated clinic hypertension may not be a benign condition.

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BACKGROUND: The objective of the present study was to identify the hemodynamic variables, that preclude the effectiveness of the counterpulsation technique. METHODS: In order to achieve high counterpulsation volume two devices were used simultaneously. The para-aortic counterpulsation device pumping 60-70 ml was implanted on the ascending aorta, and the intra-aortic balloon (20 ml) was placed in the descending aorta of 14 dogs with severe cardiogenic shock. Both devices were synchronized to provide aortic diastolic augmentation. The mechanical assistance provided by these devices was considered adequate when the mean aortic pressure during the supportive period was at least 50 mmHg, a pressure compatible with life. RESULTS: The mechanical assistance provided by the two devices was adequate in none (0%) of the cases with a systolic aortic pressure below 30 mmHg (Group I), in 71% of the cases with a systolic aortic pressure between 30-56 mmHg (Group II), and in 100% of the cases with a systolic aortic pressure above 56 mmHg (Group III). In group II the left ventricular end-diastolic pressure was higher in the cases responding adequately to mechanical assistance (Subgroup IIa) than in the ones where no adequate response was obtained (Subgroup IIb). CONCLUSIONS: The very low levels of the systolic aortic pressure was the most important factor precluding the adequate effectiveness of the counterpulsation technique.

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BACKGROUND: Morphologic changes of the vascular endothelium are common in patients with systemic sclerosis and Raynaud's phenomenon. The aim of this study was to evaluate the endothelium-dependent vasodilatation and endothelium-independent vasodilatation and to examine the effects of short-term estrogen administration on vascular responses in these patients. METHODS AND RESULTS: The study included 12 female patients with systemic sclerosis and Raynaud's phenomenon (aged 49+/-14 years) and 12 age- and sex-matched healthy control subjects. With the use of high-resolution ultrasound imaging, brachial artery diameter was measured at rest, during reactive hyperemia (endothelium-dependent response), and after administration of sublingual nitroglycerin (endothelium-independent dilatation). Intima-media thickness of the common carotid artery was also measured. Baseline diameter was similar in patients and control subjects; intima-media thickness was significantly higher in patients (0.83+/-0.3 vs 0.46+/-0.2 mm, P= .002) than in control subjects. Flow-mediated dilatation was reduced in patients (3.6%+/-7% vs 11.9%+/- 4.6%, P = .003); endothelium-independent dilatation also was reduced in patients with Raynaud's phenomenon (14%+/-7% vs 23%+/-6%, P= .003). Vascular responses in 10 patients were examined 15 minutes after administration of conjugated estrogens (25 mg intravenously); there was a significant increase of endothelium-dependent dilatation after estrogen administration (1.7%+/-4% to 6.3%+/-4%, P= .01), whereas endothelium-independent dilatation did not change (13.4%+/-8% to 15.5%+/-7%, not significant). CONCLUSIONS: Endothelium-dependent vasodilatation and endothelium-independent vasodilatation are impaired in patients with Raynaud's phenomenon secondary to systemic sclerosis, whereas intima-media thickness is increased. Short-term estrogen administration can improve endothelial dysfunction in this group of patients.

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This study examines whether a catheter mounted left intraventricular balloon may prevent left ventricular (LV) dysfunction following acute experimental myocardial infarction. In 10 anesthetized pigs, multiple coronary arterial ligations were applied around the apex of the heart. LV end-diastolic pressure (LVEDP), aortic flow (AF), and LV long and short axis fractional shortening (FS) were measured before and at 15 min intervals after ligations. At the 60th min after ligation, the LV long axis FS and AF decreased by 7.2 +/- 2.6% (p < 0.05) and 13.25 +/- 2.68% (p < 0.01), respectively, and the LVEDP increased by 4.3 +/- 1.1 mm Hg (p < 0.01) while no change was noted in the LV short axis FS. An intraventricular catheter mounted nonpulsating balloon was positioned over the endocardium of the infarcted area at the LV apex. Inflation of the nonpulsating balloon to an optimal volume, which was found to be equal to 8-10% of the LV end-diastolic volume, resulted in a reduction (by 3.8 +/- 1.2 mm Hg, p < 0.01) of the already increased LVEDP and in an increase (by 6.6 +/- 2.1%, p < 0.05) in the LV short axis FS while no statistically significant change was noted in the AF and LV long axis FS. It is concluded that an intraventricular catheter mounted balloon patch positioned over the endocardium of the infarcted area may ameliorate early LV dysfunction, possibly by interfering with the functional geometry of the LV contraction.

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