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D Bonaduce

Publications and source records attributed to D Bonaduce.

At least 55 records · Page 3Linked to original sources
PubMed1992

Effects of converting enzyme inhibition on baroreflex sensitivity in patients with myocardial infarction.

BACKGROUND: Baroreflex sensitivity provides useful prognostic information in patients after acute myocardial infarction. However, no data are available about the effects of converting enzyme inhibition on this variable. OBJECTIVES: The aim of the study was to evaluate the effects of angiotensin-converting enzyme inhibition on baroreflex sensitivity in patients after uncomplicated myocardial infarction. METHODS: Twenty-five patients after uncomplicated myocardial infarction underwent baroreflex sensitivity evaluation 72 to 96 h after symptom onset and after 4 days of captopril therapy. Twenty additional patients with the same characteristics were evaluated at the same time intervals before and after placebo administration to identify spontaneous baroreflex sensitivity variations. Baroreflex sensitivity was assessed by calculating the regression line relating phenylephrine-induced increases in systolic blood pressure to the attendant changes in the RR interval. RESULTS: The mean baroreflex sensitivity value increased after captopril administration from 6.5 +/- 4.2 to 11.8 +/- 6.1 ms/mm Hg (p less than 0.01) and in individual analyses increased by greater than 2 ms/mm Hg in 68% of patients. Mean plasma renin activity increased after captopril from 3.7 +/- 2.4 to 8.5 +/- 4.9 ng/ml per h (p less than 0.005). No difference was detectable in baroreflex sensitivity and plasma renin activity values according to the site of necrosis. In the control group, baroreflex sensitivity and plasma renin activity remained unchanged between the two studies. CONCLUSIONS: This study demonstrates that in patients with uncomplicated myocardial infarction, captopril significantly improves the chronotropic response to baroreceptor stimulation.

Adult↗
PubMed1991

Prevalence and prognostic significance of silent myocardial ischaemia detected by exercise test and continuous ECG monitoring after acute myocardial infarction.

The incidence and prognostic significance of silent myocardial ischaemia in 165 patients who survived a first acute myocardial infarction were assessed by means of maximal exercise stress test and 24 h continuous ECG monitoring performed before discharge. During the 1 year follow-up period 10 cardiac deaths occurred; moreover seven patients suffered a fatal myocardial re-infarction and 14 developed unstable angina. Cardiac death occurred in five of 40 patients (12.5%) with ST segment depression on stress test by in only three of 117 (2.6%) without ST segment changes (P less than 0.01). One-hundred-and-three of 117 patients (88.0%) without angina or ST segment depression on stress testing survived 1 year without cardiac events, compared with 24 of 40 patients (60.0%) with ST segment depression whether or not associated with angina (P less than 0.001). Cardiac death occurred in five of 25 patients (20.0%) with ST segment depression on continuous ECG monitoring, compared with five of 140 (3.6%) without (P less than 0.01). One-hundred-and-seventeen out of 140 patients (83.6%) without angina or ST segment depression survived 1 year follow-up without cardiac events, compared with 13 of 25 (52.0%) with ST segment depression with or without angina (P less than 0.01). Classifying patients in a 2 x 5 contingency table according to the occurrence of ST segment depression on exercise testing and/or ECG ambulatory monitoring, the Yates corrected chi-square test showed a significant pattern when cardiac deaths and cardiac events were considered together (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Cardiac changes induced by deconditioning in athletes: an echocardiographic and electrocardiographic study].

The relationships between echocardiographic and electrocardiographic variations and the sensibility of three different electrocardiographic criteria of left ventricular (LV) hypertrophy were assessed during deconditioning in 18 top-level oarsmen (mean age 23 +/- 4 years). After seven months of training and on the 7th and 21st deconditioning days the oarsmen underwent clinical examination, electrocardiogram (ECG) and echocardiogram with Doppler evaluation. The following ECG measurements were obtained: heart rate (HR), QTc, QRS and T waves axes, QRS and T wave angular gradients, R, S and T wave amplitude and T wave area. Moreover, the sums of S wave in lead V1 plus R wave in lead V5 or V6, of S wave in lead V1 or V2 plus R wave in lead V5 or V6, and of R wave in lead aVL plus S wave in lead V3 were calculated as indices of left ventricular hypertrophy. The following echocardiographic parameters were also analyzed: intraventricular septal (IVST) and posterior wall thickness (PWT), LV internal diameter (LVID), left ventricular mass (LVM) and volumes, LV endocardial/epicardial diastolic surface area ratio, peak systolic meridional wall stress (PSS), end-systolic stress (ESS) and mean systolic wall stress (MWSI), LV ejection fraction (EF) and total peripheral resistances (TPR); early (E) and late (A) transmitral peak flow velocity, E/A ratio. Systolic blood pressure was reduced after 3 deconditioning weeks, while diastolic blood pressure and HR were unchanged. Left ventricular mass and end-systolic volume were reduced after 1 week, while LV end-diastolic volume only after 3 weeks; therefore, EF improved at the end of the first week when TPR were lower. End-systolic stress always remained unchanged; PSS increased at 1 week and then returned to previous values. In addition, the endocardial-epicardial area ratio increased after 1 week and then returned to starting values after 3 weeks. Doppler parameters were in the normal range and remained unchanged during the study. Amplitudes of R wave in aVL, V5, V6 and of S wave in V2 did not change, while S wave amplitude in V1 and V3 decreased after three weeks and one week, respectively. The most sensible criterion for LV hypertrophy was the sum of S wave in V1 or V2 plus R wave in V5 or V6 (range from 33.3% to 22.2%); the sum of S in V1 plus R in V5 or V6 performed better than the sum of R in aVL plus S in V3.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗
PubMed1991

[Influence of age on the short- and medium-term prognosis in patients with acute myocardial infarct].

Elderly patients with acute myocardial infarction (AMI) have a higher subsequent mortality than younger ones, yet the reasons for this adverse prognosis are poorly understood. We compared the clinical course and the prognosis of 163 patients aged 40 to 69 years with 112 patients older than 70 years. During hospitalization period 15.9% of younger and 37.5% of older patients died; at 1 year follow-up the cardiac mortality rate was 8.7% in younger and 12.9% in older patients. In elderly patients a greater prevalence of female gender, diabetes mellitus, anterior myocardial infarction, atrial fibrillation and a greater incidence of heart failure and shock were observed. Multivariate stepwise analysis identified shock and heart rate greater than or equal to 90 bpm at the time of admission as the most important prognostic variables for in-hospital mortality in both groups; heart failure (Killip class II and III) was significant in younger patients, while non Q wave myocardial infarction correlated with a better prognosis in elderly. In elderly patients who survived AMI, predischarge Holter monitoring showed higher frequency and complexity of ventricular arrhythmias, and radionuclide angiography lower left ventricular ejection fraction (E.F.) values. In these patients no difference was found in E.F. values despite myocardial infarction sites. At 1 year follow-up E.F. less than 40% and ventricular arrhythmias (3-4 Moss grading system) were significantly related to prognosis in younger patients, while E.F. less than 40% and clinical signs of heart failure in elderly. Therefore, low E.F. and heart failure account for a worse prognosis in elderly patients, while ventricular arrhythmias in younger ones. The results of this study support aggressive management even in elderly patients following AMI to preserve left ventricular function. In elderly patients a large use of antiarrhythmic drugs is not recommended because of low prognostic value of ventricular arrhythmias.

Adult↗
PubMed1990

Usefulness of late coronary thrombolysis (recombinant tissue-type plasminogen activator) in preserving left ventricular function in acute myocardial infarction.

This study assesses whether administration of recombinant tissue-type plasminogen activator (rt-PA) up to 8 hours after onset of symptoms of acute myocardial infarction (AMI) may result in a significant improvement in left ventricular function. Sixty patients were classified into 3 groups: group A (n = 21) received rt-PA within 4 hours from symptom onset; the remaining 39 patients, admitted between 4 and 8 hours, were randomized into 2 groups--group B (n = 19) received rt-PA, and group C (n = 21) was treated with conventional therapy. Coronary and left ventricular angiograms were recorded 8 to 10 days after rt-PA administration. The patency rate of the infarct-related artery was 76% in group A, and 63 and 35% in group B and C, respectively. The Thrombolysis in Myocardial Infarction trial perfusion grade was higher in group A and B than in group C (A vs C: p less than 0.005; B vs C: p less than 0.01). Left ventricular ejection fraction was significantly higher in group A (60.2 +/- 10%) and B (54.7 +/- 12%) compared with group C (44.2 +/- 12%) (A vs C: p less than 0.01; B vs C: p less than 0.05). Regional wall motion of the entire ischemic zone was better in group A and B than in group C (A vs C: p less than 0.001; B vs C: p less than 0.01). In contrast, the kinesis of the central ischemic zone was significantly better in group A than in both group B and C (A vs B: p less than 0.05; A vs C: p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Angiography↗
PubMed1990

Parkinson's disease and hypotension: 24-hour blood pressure recording in ambulant patients.

Continuous intra-arterial blood pressure was recorded in 5 ambulatory patients with Parkinson's disease and in 5 control subjects. The 24-h mean systolic blood pressure was 135 +/- 7.6 mmHg in controls and 123.8 +/- 8.1 mmHg (p less than 0.01) in the parkinsonian group. Similarly, diastolic blood pressure was 89 +/- 8.1 mmHg in the control group while in the parkinsonian patients it was lower, 69.4 +/- 5.8 (p less than 0.01). Averages were also calculated for 8-h periods, the results of which indicate that both systolic and diastolic blood pressure were significantly lower in patients than in controls in all three 8-h periods of the day. We normalized the blood pressure curve to mealtimes and arousal times and did not observe any difference between parkinsonian patients and controls. This first study reporting continuous intra-arterial blood pressure measurements in ambulant parkinsonian patients demonstrates that blood pressure in such patients is lower than the mean for their age group. This finding may be of direct relevance in the management of idiopathic parkinsonism.

Adult↗
PubMed1990

Phase analysis of radionuclide angiography in acute myocardial infarction.

Standard deviation of the histogram of left ventricular phase distribution (SDP-LV) obtained by radionuclide angiography (RNA) was studied in 75 acute myocardial infarction (AMI) patients, 37 with anterior or anteroseptal (Group A) and 38 with inferior, inferolateral or posterior necrosis (Group I). In order to evaluate sensitivity, specificity and accuracy of SDP-LV compared to ejection fraction (EF) and peak filling rate (PFR), 16 controls and 29 patients with coronary artery disease with normal kinesis proved by angiography were studied. Patients were also compared according to normal or abnormal EF and PFR. Sensitivity of PFR was better than those of EF and PFR (86.6% vs 38.7% and 70.6%, respectively). Specificity of SDP-LV was 89.6%, better than that of PFR (58.6%), but just less than that of EF (93.1%). The accuracy of SDP-LV turned out to be better than those of EF and PFR (87.5% vs 53.8% and 67.3%, respectively). Ejection fraction correlated with SDP-LV in the total study population (r = -0.54, P less than 0.001), and in Groups A (r = -0.44, P less than 0.01) and I (r = -0.43, P less than 0.05); SDP-LV correlated with PFR in the total population (r = -0.35, P less than 0.05), but not in Group A or I. Mean SDP-LV was higher in Group A than I and in patients with lower EF; no difference was found among patients with different PFR values.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Effects of late administration of tissue-type plasminogen activator on left ventricular remodeling and function after myocardial infarction.

To evaluate the effects of late thrombolysis on left ventricular volume and function in acute myocardial infarction, two-dimensional echocardiography and radionuclide angiography were performed before discharge and after 1 year of follow-up study in 34 patients with acute anterior myocardial infarction. Of these, 10 admitted to the coronary care unit within 4 h from the onset of symptoms were treated with recombinant tissue-type plasminogen activator (rt-PA) (Group A) and 24 admitted between 4 and 8 h after onset were randomly assigned to receive either rt-PA (Group B, n = 12) or conventional therapy (Group C, n = 12). Seven to 10 days after admission, all patients underwent cardiac catheterization and coronary angiography. Patency of the infarct-related vessel was 70% in Group A, 66% in Group B and 33% in Group C and the average Thrombolysis in Myocardial Infarction (TIMI) coronary perfusion grade was 1.9 +/- 0.8 for Group A, 1.6 +/- 1.0 for Group B and 0.84 +/- 0.95 for Group C (Group A versus Group C p less than 0.01; Group B versus Group C p less than 0.05). At predischarge evaluation, mean left ventricular end-systolic and end-diastolic volumes were higher in Group C than in Group B (p less than 0.001 and 0.05, respectively) and Group A (p less than 0.005 for both); mean left ventricular ejection fraction at rest was lower in Group C than in Group B and Group A (p less than 0.05 for both). At 1 year follow-up study, end-systolic and end-diastolic volumes remained higher in Group C than in Group B (p less than 0.05 for both) and Group A (p less than 0.005 for end-systolic volume and p less than 0.001 for end-diastolic volume); ejection fraction at rest was lower in Group C than in Groups A and B (p less than 0.05 for both); during exercise, it increased more in Group A than in Group C (p less than 0.01). Comparison of data obtained before discharge and at the 1 year follow-up study revealed a significant differences in end-systolic volume (p less than 0.05) in Group C patients and in end-diastolic volume in patients in Groups B (p less than 0.05) and C (p less than 0.001). The beneficial effect of late thrombolysis with rt-PA may be related to a reduction in myocardial expansion and thus to a favorable influence on postinfarction left ventricular remodeling.

Coronary Vessels↗
PubMed1990

[The effects of slow-release verapamil in relation to plasma concentration in aged hypertensives. A study with continuous monitoring of arterial pressure and electrocardiogram].

Twenty-four hour ambulatory blood pressure and electrocardiographic monitoring (Oxford method) was carried out in baseline conditions and after 15 days of therapy with a once a day administration of 240 mg verapamil slow-release in 11 elderly hypertensive patients. The 24 hour electrocardiographic monitoring (but not the blood pressure monitoring) was also carried out after 30 days of therapy. High-pressure liquid chromatography plasma concentrations of verapamil and its metabolite norverapamil were compared with the blood pressure and electrocardiographic responses. Systolic and diastolic blood pressure were significantly reduced after 15 days of therapy without circadian rhythm modification; mean heart rate was reduced after 15 and 30 days and the P-Q interval prolonged. Peak verapamil and norverapamil plasma concentrations were observed 8 hours after administration; at the 25th hour, the concentrations were respectively 60.9% and 68.3% of peak value (139.5 +/- 95.4 ng/ml and 126.4 +/- 60.9 ng/ml). Plasma levels of verapamil and norverapamil significantly correlated with heart-rate decrease. No correlation was observed between drug concentrations and systolic and diastolic blood pressure. A first-degree atrioventricular block was observed in 3 patients during therapy. Supraventricular premature contractions showed a decrease after 15 and 30 days of therapy. Thus, once a day administration of verapamil slow release is an effective anti-hypertensive medication in elderly hypertensive patients. Caution should be exercised in patients with P-Q interval prolongation and sinus bradycardia.

Aged↗
PubMed1990

[Nisoldipine in the therapy of stable exercise angina: evaluation of its efficacy in ergometric tests compared with propranolol].

The safety and efficacy of a new dihydropyridine calcium antagonist, nisoldipine, were studied in comparison with propranolol, in patients with stable angina. Following 2 weeks of wash-out of the current therapy and 1 week of placebo, 26 patients underwent two cycloergometer tests, before and 2 hours after placebo administration. Subsequently, 10 mg of nisoldipine twice daily or 40 mg of propranolol three times daily were administered over a 4 week period, in a randomized single-blind fashion. Cycloergometer tests were performed after 2 and 4 weeks, before and two hours after drug administration. Two patients, one out of the nisoldipine group and one out of the propranolol, were considered drop outs. Statistical analysis of the results was performed using two-way variance analysis. With both drugs, time to 1 mm exercise induced ST-segment depression (p less than 0.01), time to angina (p less than 0.01), and exercise tolerance (p less than 0.01) improved furthermore, ST-segment and heart rate recovery time decreased (p less than 0.01). Rate-pressure product values at ischemic threshold and at peak exercise remained unchanged with nisoldipine, while significant reductions were observed with propranolol (p less than 0.01). Maximum ST-segment depression was reduced (p less than 0.01) with both drugs and a further improvement was observed two hours after drug administration (p less than 0.05). At submaximum work-load, rate pressure product values and ST-segment depression were improved with both drugs (p less than 0.01); this improvement was more evident two hours after drug administration. No significant side effects were observed with either drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[The clinical characterization and prognostic significance of episodes of transient myocardial ischemia in patients with a recent myocardial infarct].

The incidence and prognostic significance of silent myocardial ischemia were assessed in 175 patients who survived a first acute myocardial infarction (AMI). This was done by means of a 24-hour continuous ECG monitoring which was performed before discharge. Twenty-six out of 175 patients (14.8%) showed one episode or more of S-T segment depression; 19 of these reported no pain at all while the other 7 reported both painful and painless episodes. A total of 65 ischemic episodes were registered; of these 53 (81.5%) were painless and 12 (18.5%) were painful. No difference in the duration of ischemic episodes or in heart rate at the onset of S-T segment depression was detected for painless or painful episodes. The S-T segment depression episodes showed a peak in the morning but were higher in the afternoon and this circadian pattern was statistically significant both with regard to duration (p less than 0.05) and to the number of episodes (p less than 0.05). Cardiac death occurred in 5 of the 26 patients (19.2%) with S-T segment depression during continuous ECG monitoring, and in 5 of the 149 (3.4%) without S-T segment depression (p less than 0.01). In patients with ischemia duration greater than 60 min/24 hours, the mortality rate was higher (p less than 0.05). No cardiac events (unstable angina, non-fatal re-infarction, balloon angioplasty and/or coronary by-pass) occurred in 117 out of 149 patients (78.5%) without ST-segment depression, while these events were observed in 13 out of the 26 patients (50%) with ischemic episodes during Holter monitoring (p less than 0.01). Sensitivity and specificity of S-T segment depression was respectively 29.3 and 89.5% for cardiac death and cardiac events considered together.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗
PubMed1990

[A Doppler echocardiographic study of normal and dysfunctioning Carpentier-Edwards bioprostheses].

The aim of this study was to delineate the Doppler echocardiographic characteristics of normal and dysfunctioning Carpentier-Edwards bioprostheses. Echocardiographic and Doppler studies were performed on 61 mitral and 41 aortic valves; by means of on clinical evaluation, 15 mitral and 12 aortic valves were considered to be abnormally functioning. The maximum velocity (Vmax) of diastolic left ventricular inflow, pressure half-time and valve orifice area were assessed for prostheses in mitral position, while the maximum velocity (Vmax) of transaortic flow was calculated for prostheses in aortic position. Moreover, the quantitative assessment of mitral and/or aortic regurgitation was performed using the mapping technique with pulsed Doppler wave mode. Normally functioning mitral prostheses were characterized by Vmax less than 2.20 m/s and pressure half-time less than 164 ms; furthermore, mean values of Vmax and pressure half-time were significantly lower in normal than in dysfunctioning prostheses (1.70 +/- 0.33 vs 2.09 +/- 0.52 m/s; p less than 0.01 and 96.14 +/- 29.76 vs 147.87 +/- 57.41 ms; p less than 0.01 respectively). All dysfunctioning mitral valves were characterized by regurgitation graded as severe in 8 cases and moderate in 7 but only 40 and 20% of these presented respectively Vmax and pressure half-time values which were higher than those of normally functioning valves (2.20 m/s and 164 ms respectively); no pure stenosis was found. In the aortic position, normally functioning prostheses were characterized by Vmax less than 3.10 m/s. Furthermore, mean Vmax values were lower in normal than in dysfunctioning prostheses (2.55 +/- 0.53 vs 3.18 +/- 0.80; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗
PubMed1989

Myocardial hypertrophy and left ventricular diastolic function in hypertensive patients: an echo Doppler evaluation.

The presence and the characteristics of left ventricular diastolic dysfunction in mild to moderate systemic hypertension were evaluated in 13 normotensive subjects (Group I), in 12 hypertensive subjects without (Group II) and 28 with (Group III) LV hypertrophy who underwent two-dimensional Doppler echocardiographic study. Among Group III patients, a subset (n = 12) with a dilated left ventricle was identified. Diastolic filling parameters were impaired in Group III patients while, in Group II, they were intermediate between Groups I and III. In all Group III patients normalized peak filling rate (nPFR) correlated directly with mean velocity of circumferential fibre shortening (mVCF) (r = 0.55; P less than 0.001) and inversely with left ventricular mass index (LVM) (r = -0.60; P less than 0.001), left ventricular end-diastolic diameter (LVIDd) (r = -0.63; P less than 0.001), LV peak systolic stress (LVWST) (r = -0.64; P less than 0.01). A separate analysis showed that these correlations were also present in patients without left ventricular dilation; in the subset with left ventricular dilation nPFR correlated only with LVWST (r = -0.73; P less than 0.01), but not with LVM, mVCF, LVIDd. Thus, left ventricular hypertrophy is one of the major determinants of diastolic dysfunction in hypertensives; other factors influence nPFR values in hypertensive patients when the left ventricle dilates.

Adult↗
PubMed1989

[Ischemic coronary artery disease in menopause].

Women show a lower incidence of Coronary Artery Disease (CAD) and probably a better prognosis than men. However better survival rate of women tended to be obscured because they were more likely to have histories of hypertension and diabetes and to be older than men. In this paper, incidence, clinical presentation, and prognosis of CAD in women are examined. Furthermore the conflicting reports concerning the effect of estrogen use on morbidity from CAD are reported. Finally the syndrome of angina with a normal coronary arteriogram, sometimes referred to as "Syndrome X" is analyzed.

Angina Pectoris↗
PubMed1988

Diastolic function in acute myocardial infarction: a radionuclide study.

We studied left ventricular diastolic function by equilibrium gated radionuclide angiography in patients as follows: 75 with acute myocardial infarction (AMI), 35 with anterior or anteroseptal necrosis (Group A) and 40 with inferior, inferolateral, or posterior necrosis (Group I). The ejection fraction (EF) was lower in Group A than Group I (41.9 +/- 2.5 vs. 57.1 +/- 2.0%, p less than 0.001), as was peak diastolic filling rate normalized to end diastolic volume (PDFR-EDV/sec) (1.9 +/- 0.1 vs. 2.4 +/- 0.1 EDV/sec, p less than 0.05). PDFR normalized to stroke volume was similar in both groups. An excellent linear correlation was found between EF and PDFR-EDV/sec in the total study population. Isovolumic relaxation period (IRP) was beyond our upper normal value of 94 msec in 64% of patients and it was shorter in Group A than I (95.8 +/- 12.7 vs. 147.0 +/- 13.6 msec, p less than 0.05). The presence of shorter IRP in Group A than in I is probably a result of an earlier mitral valve opening as a consequence of higher left atrial pressure.

Adult↗
PubMed1988

[Different modalities of classification and prognostic significance of ventricular arrhythmias after acute myocardial infarct. Prospective study].

In our study we compared the prognostic significance of clinical variables, laboratory results and different classification models of ventricular ectopic beats recorded by means of a pre-discharge 24 hour ambulatory electrocardiographic monitoring, in 210 survivors of acute myocardial infarction. In addition a full multivariate analysis of the factors affecting survival time was carried out using Cox's proportional hazards (multiple) regression model. Multivariate stepwise discriminant analysis identified hypertension, congestive heart failure assessed by Killip class, and the grading system for ventricular arrhythmias as the most important prognostic variables. When Moss grading system for ventricular arrhythmias was used, the relative risk was a superior as heavy Moss grading system (Moss 2 vs Moss 1 and Moss 3-4 vs Moss 1, relative risk = 1.2 and 3.6 total death, respectively). Furthermore, the hazard ratio of Moss grading system was higher utilizing as comparison patients without ventricular ectopic beats (relative risk = 1.7 for Moss 2 and 5.3 for Moss 3-4) than patients with ventricular ectopic beats less than one/hour (relative risk = 1.2 for Moss 2 and 3.7 for Moss 3-4). Thus, in survivors of acute myocardial infarction, a rational and useful ventricular ectopic beats categorization includes both frequency and the presence or absence of malignant characteristics.

Adult↗