Acute changes of left atrial distensibility in congestive heart failure

BACKGROUND

Investigations of the left atrial (LA) distensibility have revealed that it plays a major role in atrial function; however, LA distensibility has not as yet been studied in congestive heart failure (CHF).

HYPOTHESIS

The study was undertaken to determine the effects of acute administration of esmolol, isosorbide dinitrate, dobutamine, and normal saline infusion on LA dimension, pressure, and distensibility.

METHODS

The study included 23 patients with CHF (18 with ischemic heart disease and 5 with idiopathic dilated cardiomyopathy). Left atrial diameters (D) and pressures (P) were recorded at rest and thereafter during acute tests. P and D data during the ascending limb of the V loop were fitted to the exponential function P = b.ead, where a is the passive elastic chamber stiffness constant and b is the elastic constant. The instantaneous diastolic LA distensibility (IDLAD) was calculated as 1/(dP/dD) = 1/a.P.

RESULTS

The constant, a, increased significantly after normal saline and esmolol infusion (p < 0.001), while it significantly decreased after isosorbide dinitrate (p < 0.001) and dobutamine administration (p < 0.05) compared with baseline. Instantaneous diastolic LA distensibility (in mm/Hg) was 0.16 at baseline; it significantly increased after isosorbide dinitrate (0.32) and dobutamine (0.24) administration, while it significantly decreased after normal saline (0.11) and esmolol (0.12) infusion (p < 0.001 for all).

CONCLUSION

In CHF, LA distensibility may acutely increase with vasodilators or inotropics or may decrease with beta blockade or volume loading.

The effect of iron overload in the hearts of patients with beta-thalassemia

BACKGROUND AND HYPOTHESIS

An important complication of beta-thalassemia is iron deposition in cardiac tissues resulting in fibrosis and dysfunction. Our aim was the investigation of the possible clinical effect of iron loading in the heart of patients with beta-thalassemia prior to the appearance of symptoms of depressed systolic function.

METHODS

Thirty-five patients with beta-thalassemia, of whom 24 had the major type (Group 1) and 11 had the intermedia type (Group 2) were studied. Eleven age- and gender-matched controls were also studied (Group 3). All patients were evaluated echocardiographically and were shown to have normal left ventricular systolic function and dimensions. Serum ferritin, atrial natriuretic peptide (ANP), left atrial diameter (LAD), peak early mitral inflow velocity (E), peak late mitral inflow velocity (A), E/A ratio, deceleration time of the mitral inflow E wave (DT), and isovolumic relaxation time (IVRT) were measured.

RESULTS

Univariate analysis showed that both groups of patients had similarly increased LAD and ANP plasma levels. Group 1 had a higher E/A ratio (2.27 +/- 0.88) SS than Group 2 (1.69 +/- 0.47, p = 0.05) and Group 3 (1.50 +/- 0.38, p = 0.01). Serum ferritin was significantly higher in Group 1 (3.526 +/- 0.352) than in Group 2 (2.808 +/- 0.288, p < 10(-5) and Group 3 (2.139 +/- 0.124, p < 10(-5). Multivariate analysis showed that ANP is a factor that is affected by the LAD and E/A ratio and that serum ferritin levels affect the LAD and E/A ratio.

CONCLUSIONS

Although LAD and ANP levels are increased in patients with beta-thalassemia, the increased serum ferritin levels of patients seem to affect left atrial size and E/A ratio. ANP secretion is consecutively affected by these factors.

QRS prolongation on the signal-averaged electrocardiogram versus ST-segment changes on the 12-lead electrocardiogram: which is the most sensitive electrocardiographic marker of myocardial ischemia?

BACKGROUND

ST-segment changes and QRS prolongation are electrocardiographic (ECG) markers of myocardial ischemia.

HYPOTHESIS

This study was undertaken to investigate the appearance of QRS duration changes with or without concomitant ST-segment changes during a typical anginal episode.

METHODS

For this purpose, 126 patients underwent 12-lead surface ECG and signal-averaged electrocardiogram (SAECG) during typical anginal pain as well as at the time the patient was asymptomatic. In both periods, QRS duration and ST-segment changes were evaluated. All patients underwent cardiac catheterization.

RESULTS

Of the 126 patients, 108 (86%) had coronary artery disease (CAD), whereas the remaining 18 (14%) patients had normal coronary arteriograms. During typical anginal pain, 75 of the 108 (70%) patients with CAD and 2 of the 18 (11%) patients with normal coronary arteriograms developed QRS prolongation, whereas 60 of the 108 (56%) patients with CAD and 2 of the 18 (11%) patients with normal coronary vessels developed ST-segment changes. Thus, the sensitivities of QRS prolongation measured by SAECG and of ST-segment changes on the surface ECG for the detection of myocardial ischemia were found to be 70 and 56%, respectively, (p < 0.01), whereas the specificities were both found to be 89% (p = NS).

CONCLUSIONS

During typical anginal pain, QRS prolongation on the SAECG is more sensitive than are ST-segment changes on the ECG for the detection of myocardial ischemia.

Ischemia-induced reflex sympathoexcitation during the recovery period after maximal treadmill exercise testing

BACKGROUND

Heart rate variability (HRV) analysis is problematic during maximal treadmill exercise testing (ET) due to rapidly changing heart rate.

HYPOTHESIS

The aim of this study was to assess HRV spectral components during treadmill ET in patients with coronary artery disease (CAD) and in healthy controls, and to search for possible differences between the two groups.

METHODS

Thirty patients with CAD and 30 age-matched healthy controls underwent symptom-limited ET and continuous electrocardiographic monitoring. For adequate assessment of HRV during maximal ET, we calculated the HRV measures [normalized units (NU)]--low-frequency (0.040-0.150 Hz) power (LF), high-frequency (0.150-0.400 Hz) power (HF), and the LF/HF ratio--from all the sequential stages of the ET with limited changes (20 beats/min) in heart rate (stress 80-100, 100-120, 120-140, 140-160, 160-180/recovery 180-160, 160-140, 140-120, 120-100, 100-80).

RESULTS

Both LF and HF were found to decrease gradually during ET and to increase during the recovery period in both patients and controls (p < 0.001). LF values were higher during the recovery period than during the respective stages of exercise time in both patients and controls, and LF/HF ratio was higher during recovery in patients only.

CONCLUSIONS

During maximal ET (1) vagal tone withdraws during the exercise time and increases during the recovery period; (2) the sympathetic activity predominates during the recovery period, especially in patients with CAD and exercise-induced myocardial ischemia. This finding raises the possibility of ischemia-induced cardiocardiac sympathetic excitatory reflexes.

Effect of angiotensin-converting enzyme inhibitor on collagenolytic enzyme activity in patients with acute myocardial infarction

Matrix metalloproteinases and their tissue inhibitors are key enzymes degrading myocardial collagen in acute myocardial infarction (AMI). The aim of the present study was to determine whether angiotensin-converting enzyme inhibitors (ACEI) influence collagenase-1 (MMP-1) and their tissue inhibitor (TIMP-1) activity in AMI patients. Plasma levels of MMP-1, TIMP-1 and MMP-1/TIMP-1 complex were measured in 24 patients (aged 58.4 +/- 13.9 years) with AMI. Thirteen patients received perindopril 4 mg/day (group A) and 11 did not (group B). Plasma samples collected on admission and at 0, 3, 6, 9, 12, 18, 24, 36 and 48 hours and on days 3, 4, 5, 7, 15 and 30 thereafter were analyzed by relevant ELISA kits. Ejection fraction (EF) was assessed by ventriculography and end-diastolic diameter (EDD) echo-study on days 6 and 30. Values of collagenolytic enzymes of group A compared with those in group B were on average lower by 34%, 18.3% and 40%, respectively. The difference in values between groups at 0 h, 3 h and 9 h was significant (p < 0.048). ANOVA repeated measurement analysis showed significance within subjects for MMP-1 alone (p < 0.043) and for MMP-1 and ACEI (p < 0.046), while for TIMP-1 and MMP-1/TIMP-1 complex significance was only p < 0.0009. Regarding EDD changes, patients in group A showed minimal or no changes (51.23 +/- 1.8 mm to 51.6 +/- 2.13 mm), their EF was 38.8% and infarct size was medium to large. In contrast, group B showed a trend to increase EDD (41 +/- 0.78 mm to 42.33 +/- 0.59 mm), their EF was 50.5% and infarct size was small to medium. In conclusion, early initiation of ACEI treatment reduces collagenolytic activity. This effect may be considered an alternative mechanism for beneficial effects on postinfarction remodeling.

The association between occupational stress and the risk of developing acute coronary syndromes: the CARDIO2000 Study

OBJECTIVE

The aim of this study was to investigate the association between occupational stress and the risk of developing acute coronary syndromes, in a population-based sample of patients and controls.

METHODOLOGY

During 2000-01, a case-control study was conducted (CARDIO2000). A random and stratified sample of 848 middle aged patients with a first of an acute coronary syndrome and 1078 cardiovascular disease free participants, matched with the patients by gender, age and region, was selected from all regions of Greece. In addition to the common cardiovascular risk factors, the effect of occupational stress on coronary risk was evaluated, after taking into account income, marital status, educational and occupational level of the participants. The levels of occupational stress were measured by administering to the individuals a self-reported questionnaire.

RESULTS

After controlling for age, gender and region, by design, and the presence of smoking, hypertension, hypercholesterolaemia, diabetes mellitus, physical activity status, educational and financial status and nutritional habits, multivariate analysis showed that the levels of occupational stress are positively associated with the risk of developing acute coronary syndromes in the investigated sample (Odds Ratio = 2.2, p < 0.01). Moreover, the presence of occupational stress seems to affect more significantly males than females, smokers than non-smokers, hypertensives than normotensives and high alcohol consumers compared to low alcohol consumers.

CONCLUSIONS

Although the design of the present study does not provide evidence of causality, a strong positive association between occupational stress and acute coronary syndromes seems to exist. Thus, public health policies should take into account lifestyle conditions related to work in the design of preventive strategies at the primary level.

Neurocardiogenic syncope: aetiology and management

Neurocardiogenic syncope is the most common cause of syncope presenting in the outpatient setting. It is usually encountered among individuals without an underlying heart disease, but not uncommonly participates in the syncope mechanism of patients with an obstructive or an arrhythmic cardiac cause for syncope as well. The vasovagal event is caused by a transient profound hypotensive reaction most commonly associated with inappropriate bradycardia resulting from activation of a complex autonomic reflex. The pathophysiology of neurocardiogenic syncope has been elucidated by tilt table testing, a noninvasive and well-tolerated method for reproducing the event in susceptible individuals. Although the majority of people with vasovagal fainting need no specific treatment, treatment is required for those presenting with problematic features such as frequent events accompanied by trauma or accidents, and occasionally by a severe cardioinhibitory pattern response. A number of different drugs have been proposed to favourably act on different aspects of the neurocardiogenic reflex but only a few randomised, placebo-controlled, drug-specific trials are currently available. Alternatively, cardiac pacing has also been introduced for patients who have symptoms that are drug-refractory or for those with a severe cardioinhibitory hypotensive response. The selection of the appropriate treatment plan should be individualised after consideration of patient history, clinical characteristics and preference, results of the baseline tilting study, and the existing evidence from the few randomised, controlled studies performed so far.

The effect of short-term depressive episodes on the risk stratification of acute coronary syndromes: a case-control study in Greece (Cardio 2000)

OBJECTIVE

The aim of this study is to evaluate the effect of recent depressive episodes on coronary risk, taking into account the presence of several cardiovascular risk factors and various lifestyles, and social conditions that aggregate in the Greek population.

METHODS AND RESULTS

CARDIO2000 is a matched case-control study consisting of 750 patients with a first event of acute coronary syndrome and 778 cardiovascular disease-free hospitalized subjects, randomly and stratified selected from several Greek regions. Assessment of depressive symptoms, during the past month, was based on the CES-D Scale (Radloff S, 1977). 158 (21%) coronary patients and 74 (9%) controls had short-term depressive symptoms (P<0.001). A recent depressive episode increases coronary risk by 12%, after adjusting for several confounders, while the previous outcome seems to differ significantly between sexes (OR-men = 1.09 vs. OR-women = 1.19, P<0.01). The effect of the interaction between depression and various components of social class (education, occupation, income) increases the coronary risk from 55% to 132%, while the interaction with marital status increases the previous risk by 167%, in divorced/widowed men, and by 123%, in women. Also, significant additive effects were observed between depression and smoking (25% increased coronary risk per pack-year), alcohol consumption (+97%), physical inactivity (+137%) and obesity (+127%).

CONCLUSION

This study showed the moderate effect of recent depression on the risk of developing non-fatal acute coronary syndromes in the investigated population. Also, sex differences and the additional effect of the interactions between short-term depressive episodes and several emerging or established cardiovascular risk factors occurred.

In-hospital mortality of habitual cigarette smokers after acute myocardial infarction. The 'smoker's paradox' in a countrywide study

AIMS

Habitual cigarette smokers, paradoxically, present improved short-term prognosis after acute myocardial infarction, a phenomenon often termed "smoker's paradox". We sought to examine cigarette smokers' post-infarction survival advantage in a countrywide survey of unselected, consecutive patients presenting with acute myocardial infarction.

METHODS AND RESULTS

The study population was derived from the registry of the Hellenic study of acute myocardial infarction, which recruited 7433 consecutive patients with acute myocardial infarction from 76, out of a total of 86, hospitals countrywide. Cigarette smokers presented with lower unadjusted mortality rates (7.4% vs 14.5%, P<0.001), were younger, predominantly of male gender and were less likely to suffer from diabetes mellitus and arterial hypertension. When all univariate predictors of poor outcome were included as covariates in multivariate analysis, smoking status was not significantly associated with inhospital mortality (relative risk=1.12, 95% CI=0.86-1.44, P=0.399). The beneficial effect of thrombolytic therapy was independent of the smoking status in both univariate and multivariate analysis.

CONCLUSION

Unadjusted mortality rates are significantly lower in smokers, but age accounted for much of their seemingly improved outcome. When a number of additional clinical variables were taken into consideration, no significant influence of habitual smoking on early outcome following acute myocardial infarction was observed.

Evolutionary pattern and prognostic importance of heart rate variability during the early phase of acute myocardial infarction

AIMS

To investigate the evolution of time domain heart rate variability in the early phase of acute myocardial infarction (MI) and assess its prognostic ability.

METHODS

We analysed several measures of heart rate variability (SDNN, SDANN, SDNN index, RMSSD) in 138 patients at days 0, 1 and 5+/-1 after hospital admission for acute MI. Results were correlated with infarct site, clinical variation and clinical outcome (death, MI, PTCA, CABG surgery).

RESULTS

Measures of heart rate variability (SDNN, SDANN and SDNN index) declined during the first 24 h after acute MI (P<0.01) and increased to admission levels after about 5 days. SDNN values on day 0, 1 and 5 respectively were: 86+/-35, 75+/-28 and 87+/-27 ms. Patients with anterior infarction had lower heart rate variability than patients with inferior infarction on all test days but similar evolution patterns. After 3 years of follow-up there were 12 cardiac deaths (8.7%) and six resuscitated arrests and 33 (24%) new MIs, or revascularisation procedures. The evolutionary pattern of heart rate variability was similar in survivors to those who died although values were generally lower. Mortality was significantly higher in the group with SDNN<50 ms at day 1 (P<0.01) and 5 (P<0.05), but not at day 0.

CONCLUSIONS

Our findings show that autonomic imbalance, already evident on the day of the acute event, progresses further over the next 24 h and recovers over the next few days. Low heart rate variability as early as 24 h after acute MI may be a useful predictor of cardiac mortality and contribute to the early risk stratification and therapeutic management of patients.

Increased temperature of malignant urinary bladder tumors in vivo: the application of a new method based on a catheter technique

PURPOSE

The aim of this study was to investigate the existence of any thermal difference between malignant tumors and inflammatory benign lesions of the human urinary bladder and to determine whether it correlates with tumor angiogenesis quantification.

PATIENTS AND METHODS

A new method, developed in our institute, is introduced to detect temperature in human urinary bladder, in vivo. This method is based on a thermography catheter. We calculated the differences of the temperature of the solid tumor and of a normal area (Delta T) on 20 subjects (mean age, 72.5 years; 95% confidence interval [CI], 68.5 to 76.4). According to the biopsy histology, Eight (40%) patients had benign tumors, and 12 (60%) had malignant tumors.

RESULTS

We found significant differences of Delta T between patients with benign and malignant tumor (P <.001). Also, differences were found for the mean values of angiogenesis level between malignant and benign tumors (P =.0261), and a moderated positive correlation was estimated between the degree of angiogenesis and Delta T (P =.02). Based on logistic regression analysis, we found that a 1-degree increase of Delta T triples the odds of a patient having a malignant tumor (odds ratio = 2.91; 95% CI, 1.97 to 7.78; P <.001), adjusted for the degree of angiogenesis (P =.0236) and the grade of tumor (P <.001). A threshold point of Delta T = 0.7 degrees C was determined, with sensitivity 83% and specificity 75%.

CONCLUSION

These findings suggest that the calculated difference of temperature between normal tissue and neoplastic area could be a useful criterion in the diagnosis of malignancy in tumors of the human urinary bladder.

Subpectoral cardioverter-defibrillator implantation using a lateral approach

INTRODUCTION

Third-generation cardioverter-defibrillators have revolutionized management of ventricular tachyarrhythmias. Implantation can be performed in the electro-physiology laboratory, with minimal morbidity. Generator size has shrunk to the point that subcutaneous implantation is feasible and safe, even under local anesthesia. The prepectoral technique, however, is associated with increased mechanical stress to the subcutaneous tissue and can predispose to device erosion or infection. These complications may be avoided by submuscular placement. Among subpectoral techniques, the lateral approach offers unrestricted ability to deploy patches or array electrodes, should the need arise, and may represent the optimal implant technique under some circumstances.

METHODS

We studied 29 male patients, aged 29-78 years, who presented with syncope or sustained ventricular tachycardia, and underwent subpectoral defibrillator implantation under general anesthesia or conscious sedation. All devices were third-generation active can systems with biphasic shock capability. Six dual-chamber defibrillators were used.

RESULTS

Subpectoral implantation was successful in all cases, with an estimated blood loss of 28+/-17 mL and no immediate complications. Except for one patient who developed twiddler's syndrome and ultimately required revision to a subcutaneous pocket, the implant site was tolerated well, and no limitation in the range of motion of the upper limb was observed during 20 months of follow-up.

CONCLUSIONS

Subpectoral implantation using a lateral approach is technically straightforward and can be applied globally, with modest additional resource and equipment requirements. Familiarity with this approach can maximize the likelihood of successful defibrillator implantation in the electrophysiology laboratory.

Closed relation between carotid and ascending aortic atherosclerosis in cardiac patients

BACKGROUND

Carotid atherosclerosis and aortic atherosclerosis are both associated with coronary artery disease and cerebral thromboembolism. However, the relationship between asymptomatic carotid and aortic atherosclerosis is not well known.

METHODS AND RESULTS

Sixty-two consecutive cardiac patients (mean age 57 years) without a history of atherosclerotic cardiovascular disease who were referred for transesophageal echocardiography were included. By means of a high-resolution ultrasound technique, normal carotid arteries were found in 12 patients (19.4%), whereas 15 patients (24. 2%) had increased intima-media thickness, and the remaining 35 patients (56.5%) had atherosclerotic plaques (intima-media thickness >/=1.3 mm). Transesophageal echocardiography characterized ascending aortic intimal morphology as normal in 1 patient (1.6%), as thickening in 22 patients (35.5%), and as atherosclerotic plaques in 39 patients (62.9%). Patients with both carotid and aortic plaques were older compared with patients without plaques; also, a higher percentage of patients with carotid and aortic plaques suffered from hypertension and diabetes mellitus compared with patients without plaques (P:<0.001). The incidence of carotid plaques was 74.3% (29 of 39 patients) in the subgroup with aortic plaques; there was a stepwise increase in the percentage of patients with carotid plaques among the patients with increasing grades of aortic atherosclerosis. Furthermore, the incidence of ascending aortic plaques was 82.8% (29 of 35 patients) in the subgroup with carotid plaques. Regression analysis revealed that age and carotid plaques were independently related to the presence of aortic plaques. In the entire study population, the presence of carotid plaques had a high positive predictive value (83%), an acceptable sensitivity (75%) and specificity (74%), and a relatively low negative predictive value (63%) for the presence of aortic plaques.

CONCLUSIONS

In cardiac patients without clinical evidence of atherosclerotic cardiovascular disease, a high prevalence of combined aortic and carotid plaques were detected. The presence of carotid plaque reflects the presence of aortic plaque, whereas the absence of carotid plaque may not reflect the absence of aortic plaque.

Microalbuminuria is associated with abnormal thoracic aortic mechanics in essential hypertension

In a population of 162 patients with currently untreated essential hypertension, those with microalbuminuria (n = 75) had significantly impaired elastic properties of the proximal ascending thoracic aorta compared with their normoalbuminuric counterparts (n = 87), whereas urinary albumin excretion was a significant predictor of aortic mechanics in the entire population. Impaired aortic mechanics in microalbuminuric hypertensives were not fully accounted for by clustering of classic risk factors for atherosclerosis, and constitute a finding that may entail additional long-term cardiovascular risk in this subgroup of patients.

Retrograde nontransseptal balloon mitral valvuloplasty by the brachial artery approach

Retrograde nontransseptal balloon mitral valvuloplasty is a purely transarterial technique for percutaneous treatment of mitral stenosis. We report the first use of this technique via the brachial artery for a patient with aortoiliac atherosclerosis, and we comment on the difficulties and perspectives of this approach.

The role of carotid atherosclerosis in the distinction between ischaemic and non-ischaemic cardiomyopathy

AIM

Sometimes ischaemic cardiomyopathy is a result of severe coronary artery disease of an occult course, without typical symptoms or evidence of myocardial infarction. This form of presentation is usually indistinguishable from non-ischaemic dilated cardiomyopathy. Carotid bifurcation atherosclerosis and coronary artery disease have been shown to be strongly associated. We prospectively examined the value of extracranial carotid atherosclerosis in the distinction between ischaemic and non-ischaemic aetiology in patients with clinically unexplained cardiomyopathy.

METHODS AND RESULTS

Seventy-eight patients with undetermined dilatation and diffuse impairment of the left ventricular contraction were studied within 28 months. They underwent carotid scan and coronary arteriography. Carotid atherosclerosis was found to be very common in ischaemic and rare in non-ischaemic cardiomyopathy. The presence of at least one abnormal carotid finding (intima-media thickness >1 mm, plaques, severe carotid stenosis) was 96% sensitive and 89% specific for ischaemic cardiomyopathy.

CONCLUSION

Carotid scanning may be a useful screening and decision making tool in patients with cardiomyopathy of indecisive cause. Patients with carotid atherosclerosis are likely to suffer from severe coronary artery disease. Coronary angiography and subsequent myocardial viability studies, when indicated, could be considered early during their evaluation. In contrast, a negative carotid scan predicts non-ischaemic cardiomyopathy.

Prevalence of autoantibodies against contractile proteins in coronary artery disease and their clinical implications

In this initial study, we found that autoantibodies against actin and myosin were present during and after an acute coronary syndrome. Moreover, they correlated with persistent troponin-I elevation at follow-up, and with late myocardial infarction.

Mild left ventricular hypertrophy in essential hypertension: is it really arrhythmogenic?

Left ventricular hypertrophy (LVH) has been associated with an increased incidence of ventricular arrhythmias and sudden cardiac death in hypertensive patients. However, it is not known whether this relationship exists in early asymptomatic hypertensives with mild LVH. We prospectively examined 100 consecutive patients with essential hypertension, 35 without and 65 with mild LVH on echocardiography. All underwent a detailed noninvasive arrhythmia work-up and were subsequently followed-up for 3 +/- 1 years in an ambulatory hypertension clinic. None of the 12-lead electrocardiographic parameters examined differed between the two hypertensive groups. A similarly low incidence of simple forms of ventricular ectopy was present in both groups, whereas complex forms of ventricular ectopy were extremely rare in either group. The signal-averaged electrocardiographic parameters examined were also not significantly affected by the presence of mild LVH. Arrhythmia-related symptoms or malignant ventricular arrhythmia events were not observed in either group of patients during follow-up with antihypertensive treatment. The latter resulted in LVH regression in the 65 patients with mild LVH at baseline. It appears that mild LVH among ambulatory hypertensive patients does not carry an additive arrhythmogenic risk and can be successfully reversed with the appropriate antihypertensive therapy, with no need of additional antiarrhythmic management.

Antithrombotic therapy in heart failure: a randomized comparison of warfarin vs. aspirin (HELAS)

It is uncertain whether anti-thrombotic treatment reduces the incidence of thrombo-embolism in patients with heart failure, so there is a need for a large scale controlled study to assess the effects of anti-thrombotic therapy in this setting. We report the design of a randomized controlled multicenter double blind trial examining the effects of aspirin, warfarin and placebo in patients with heart failure on the risk of thrombo-embolism. We planned to recruit 6000 patients with heart failure without contraindications to anticoagulants or antiplatelet agents and to follow them for a mean time of 2 years following randomization. The study was planned to determine the rate of thrombo-embolic and haemorrhagic events and death among patients randomized to aspirin, warfarin and placebo, stratified according to the presence or absence of underlying coronary disease. Ancillary studies parallel to the main study will attempt to identify clinical and echocardiographic risk factors for thrombo-embolism and will also examine whether hemostatic or neurohormonal mechanisms contribute to an increase in the risk of thrombo-embolism in patients with heart failure. We hoped that the results of the study would improve the clinical management and cost-effectiveness of treatment for patients with heart failure. However, the recruitment of patients proved more difficult than expected and a number of centers decided not to participate. To avoid a great delay it was decided by the principal investigators and submitted to the executive committee to terminate enrolment in this study when 300 patients had been enrolled, and accept that this is a pilot study.

Effects of ischemia on P wave dispersion and maximum P wave duration during spontaneous anginal episodes

P wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P wave duration, and maximum P wave duration (P maximum) are electrocardiographic (ECG) markers that have been used to evaluate the discontinuous propagation of sinus impulses and the prolongation of atrial conduction time, respectively. To study the effects of myocardial ischemia on P dispersion and P maximum, 95 patients with coronary artery disease (CAD) and typical angina pectoris and 15 controls with angina like symptoms underwent 12-lead surface ECG during and after the relief of pain. During pain and during the asymptomatic period, P maximum and P dispersion were calculated from the averaged complexes of all 12 leads. P dispersion increased significantly during spontaneous angina (45+/-17 ms) compared to the asymptomatic period (40+/-15 ms), P < 0.001 only in the patient group. Both P maximum and P dispersion showed higher values during angina in those patients who developed diffuse ischemia, as estimated with ST segment changes in multiple ECG leads. P dispersion showed higher values during the anginal episode in patients with left ventricular dysfunction, independently of the presence of a previous myocardial infarction. Atrial conduction abnormalities, as estimated with P maximum and particularly P dispersion, are significantly influenced by myocardial ischemia in patients with CAD and spontaneous angina.

Significance of exercise-induced simultaneous ST-segment changes in lead aVR and V5

This study was undertaken to investigate the ability of the exercise-induced ST depression in lead V5 and concomitant ST elevation in lead aVR for the identification of the significantly narrowed coronary artery in patients with single vessel disease. We studied 229 consecutive patients who developed the aforementioned exercise-induced electrocardiographic changes. All underwent Thallium-201 scintigraphy and coronary arteriography. Patients were divided into three groups. In group A, 58 patients with ST depression in V5 and ST elevation in aVR, in group B 149 patients with ST depression in V5 without ST elevation in aVR, and in group C 22 patients with ST elevation in aVR without ST depression in V5 induced with exercise, were included. In group A, 81% of the patients while in group B, 29% and in group C only 18% of the patients had left anterior descending artery disease. According to Thallium-201 scintigraphy, 80% of the group A, 27% of the group B and 12% of the group C patients developed myocardial ischemia in areas supplied by the left anterior descending artery. Thus, exercise-induced ST depression in V5 and concomitant ST elevation in aVR, may detect left anterior descending artery significant stenosis in patients with single vessel disease.

Improved detection of coronary artery disease by exercise electrocardiography with the use of right precordial leads

BACKGROUND

Exercise electrocardiography is an perfect test for the detection of coronary artery disease. We attempted to improve the diagnostic accuracy of exercise testing as a noninvasive method for the detection of coronary artery disease by using a combination of the left and right precordial leads.

METHODS

We studied 245 patients (218 men and 27 women) ranging from 32 to 74 years of age (mean [+/-SD], 52+/-8) who underwent treadmill exercise testing, thallium-201 scintigraphy, and coronary arteriography. During exercise testing, each patient had one electrocardiogram recorded with the standard 12 leads and 3 right precordial leads (V3R, V4R, and V5R), with the results for each set of leads recorded and analyzed separately.

RESULTS

On the basis of coronary arteriography, 34 patients had normal coronary arteries, 85 had single-vessel disease, 84 had two-vessel disease, and 42 had three-vessel disease. The sensitivities of the standard 12-lead exercise electrocardiogram, exercise electrocardiography incorporating right precordial leads, and thallium-201 scintigraphy were 52 percent, 89 percent, and 87 percent, respectively, for the detection of single-vessel disease; 71 percent, 94 percent, and 96 percent for the detection of two-vessel disease; 83 percent, 95 percent, and 98 percent for the detection of three-vessel disease; and 66 percent, 92 percent, and 93 percent for the detection of any coronary artery disease. The specificities of the three methods for the detection of any coronary artery disease were 88 percent, 88 percent, and 82 percent, respectively.

CONCLUSIONS

Use of right precordial leads along with the standard six left precordial leads during exercise electrocardiography greatly improves the sensitivity of exercise testing for the diagnosis of coronary artery disease.

Exercise-induced ST-segment changes in lead V1 identify the significantly narrowed coronary artery in patients with single-vessel disease: correlation with thallium-201 scintigraphy and coronary arteriography data

We investigated the correlation of exercise-induced ST-segment changes in lead V1, with the detection of the significantly narrowed vessel that induced ischemia during exercise in myocardial areas supplied by this vessel. We studied 198 patients who underwent exercise testing, thallium-201 scintigraphy, and coronary arteriography. The patients were divided into three groups. In group 1 (ST-segment elevation in lead V1), 84% had left anterior descending coronary artery disease (P<.001); in group 2 (ST-segment depression in lead V1), 76% had right coronary artery disease (P<.001); and in group 3 (no ST-segment changes in lead V1), there were no significant differences concerning the narrowed vessel. Thallium-201 scintigraphy data confirmed the existence of the reversible perfusion defect(s) in an area(s) of myocardium supplied by the respective coronary arteries (P<.001). Exercise-induced ST-segment elevation or depression in V1 may identify the obstructed vessel in patients with single-vessel disease and without prior myocardial infarction.

Effects of pravastatin on thoracic aortic atherosclerosis in patients with heterozygous familial hypercholesterolemia

Data regarding the effects of plasma lipid lowering on the evolution of thoracic aortic atherosclerosis (TAA) are scarce. In this study, we performed transesophageal echocardiography to characterize TAA in 16 newly diagnosed patients with heterozygous familial hypercholesterolemia and to follow its evolution after 2 years of statin treatment. TAA was graded as follows: grade I = normal intima; grade II = increased intimal echo density without thickening; grade IIIA = increased intimal echo density with single atheromatous plaque < or = 3 mm; grade IIIB = multiple plaques < or = 3mm; grade IV = > or = 1 plaque >3 mm; and grade V = mobile or ulcerated plaques. Baseline aortic intimal morphology was grade I in one patient, grade II in 4, grade IIIA in 6, grade IIIB in 3, and grade IV in 2 patients. Hypolipidemic treatment resulted in significant reductions in plasma total cholesterol and low-density lipoprotein (LDL) cholesterol. Follow-up aortic morphology was grade I in 5 patients, grade II in 2, grade IIIA in 3, grade IIIB in 3, and grade IV in 3 patients. TAA remained stable in 7 patients, progressed in 3, and regressed in 6 patients. TAA evolved in a uniform manner in the ascending aorta, aortic arch, and descending aorta. Patients with TAA regression were younger (39+/-14 vs 52+/-8 years, p=0.038) and had a greater decrease in plasma LDL cholesterol as a result of treatment (138+/-56 vs 73+/-55 mg/dl, p=0.036) than patients with TAA stability or progression. These observations support the hypothesis that hypolipidemic treatment may favorably affect the course of TAA in patients with heterozygous familial hypercholesterolemia.

Cardiomyopathy due to a pheochromocytoma. A reversible entity

A 45-year-old male presented with acute pulmonary oedema, chest pain and electrocardiographic manifestations of acute myocardial ischaemia in the setting of hypertension crisis from a hyperfunctioning large left-sided pheochromocytoma. Coronary artery disease was excluded on the basis of thallium stress testing and coronary angiography. The latter revealed a picture consistent with dilated cardiomyopathy. After surgical resection of the tumour, both the hypercatecholaminaemia and the arterial hypertension subsided promptly with gradual improvement of the cardiomyopathy and complete resolution of the congestive heart failure symptoms.

Regression of left ventricular hypertrophy results in improvement of QT dispersion in patients with hypertension

OBJECTIVES

Increased QT dispersion has been considered as predisposing to ventricular arrhythmias in hypertrophic cardiomyopathy, congestive heart failure, and coronary artery disease. An increased QT dispersion has also been found in hypertensive patients with left ventricular hypertrophy (LVH). The data on the effect of LVH regression on QT dispersion are limited.

METHODS AND RESULTS

To assess the relation of LVH regression and QT dispersion decrease, 68 patients (42 men and 26 women, mean age 56.3+/-9.5 years) with uncomplicated essential hypertension were studied. All underwent full electrocardiographic and echocardiographic studies at baseline and after 6 months of monotherapy, 29 with angiotensin-converting enzyme inhibitors and 39 with calcium antagonists. QT dispersion was calculated by subtracting the shortest QT from the longest QT, in absolute value (QTmax - QTmin). It was also corrected with Bazett's formula (QTc dispersion). Left ventricular mass index was assessed according to the Devereux formula. After treatment, LVH decreased with both angiotensin-converting enzyme inhibitors (from 155 to 130 g/m2, P < .001) and calcium antagonists (156 to 133/92/m2, P < .001). QT dispersion decreased both after angiotensin-converting enzyme inhibitor treatment (from 82 to 63 ms) and calcium antagonist treatment (from 77 to 63 ms, both P < .001 ). There was a significant correlation of QT dispersion and left ventricular mass after therapy (r = 0.36, P < .005). There was a correlation of the degree of LVH and QT dispersion decrease (r = 0.27, P < .05).

CONCLUSIONS

It is concluded that LVH regression influences AQT favorably. Its prognostic value has yet to be determined.

Differentiating thrombus from pannus formation in obstructed mechanical prosthetic valves: an evaluation of clinical, transthoracic and transesophageal echocardiographic parameters

OBJECTIVES

We sought to determine the clinical and echocardiographic parameters that differentiate thrombus from pannus formation as the etiology of obstructed mechanical prosthetic valves.

BACKGROUND

Distinction of thrombus from pannus on obstructed prosthetic valves is essential because thrombolytic therapy has emerged as an alternative to reoperation.

METHODS

We analyzed clinical, transthoracic and transesophageal echocardiography (TEE) data in 23 patients presenting with 24 obstructed prosthetic valves and compared the findings to pathology at surgery.

RESULTS

Fourteen valves had thrombus and 10 had pannus formation. Patients with thrombus had a shorter duration from time of valve insertion to malfunction, shorter duration of symptoms, but similar New York Heart Association functional class at the time of operation. Patients with thrombus had a lower rate of adequate anticoagulation (21% vs. 89%; p=0.0028). Pannus formation was more common in the aortic position (70% vs. 21%; p=0.035). Abnormal prosthetic valve motion was detected by TEE in all cases with thrombus formation but in 60% with pannus (p=0.0198). Thrombi were larger than pannuses (total length 2.8+/-2.47 cm vs. 1.17+/-0.43 cm; p=0.038). This was mostly due to extension of thrombi into the left atrium in prosthetic mitral valves. Thrombi appeared as a soft mass on the valve in 92% of cases, whereas 29% of pannuses had a soft echo density (p= 0.007). Ultrasound video intensity ratio, derived as the videointensity of the mass to that of the prosthetic valve, was lower in the thrombus group (0.46+/-0.14 vs. 0.71+/-0.17, p=0.006). A videointensity ratio of <0.70 had a positive predictive value of 87% and a negative predictive value of 89% for thrombus. Duration from onset of symptoms to reoperation of <1 month separated thrombus from pannus formation. The best objective clinical parameter for prediction of thrombus was inadequate anticoagulation, whereas the best TEE parameters were qualitative and quantitative ultrasound intensity of the mass. The presence of either inadequate anticoagulation or a soft mass by TEE improved the predictive power of either parameter alone and was similar to that of ultrasound videointensity ratio.

CONCLUSIONS

Duration of symptoms, anticoagulation status and qualitative and quantitative ultrasound intensity of the mass obstructing a mechanical prosthetic valve can help differentiate pannus formation from thrombus and may therefore be of value in refining the selection of patients for thrombolytic therapy of prosthetic valve obstruction.

Retrograde nontransseptal balloon mitral valvuloplasty: immediate results and intermediate long-term outcome in 441 cases--a multicenter experience

OBJECTIVES

Our aim was to present the immediate and intermediate long-term results of the application of retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) in four cooperating centers from Greece and India.

BACKGROUND

RNBMV is a purely transarterial method of balloon valvuloplasty, developed with the aim to avoid complications associated with transseptal catheterization. Only single-center experience with RNBMV has been previously reported.

METHODS

The procedure was attempted in 441 patients with symptomatic mitral stenosis (320 women, 121 men, mean age [+/-SD] 44+/-11 years, mean echocardiographic score [+/-SD] 7.7+/-2.0) from 1988 to 1996. Three hundred eighty-five patients with successful immediate outcome were followed clinically for a mean [+/-SD] of 3.5+/-1.9 (range, 0.5-9.1) years.

RESULTS

A technically successful procedure was achieved in 388 (88%) cases. The echocardiographic score (p < 0.001), male gender (p=0.005), preprocedural mitral regurgitation (p=0.007) and previous surgical commissurotomy (p=0.029) were unfavorable predictors of immediate outcome. Complications included death (0.2%), severe mitral regurgitation (3.4%) and injury of the femoral artery (1.1%). Event-free (freedom from cardiac death, mitral valve surgery, repeat valvuloplasty and NYHA class > II symptoms) survival rates (+/-SEM) were 100%, 96.9+/-0.9%, 89.8+/-1.9% and 75.5+/-5.5% at 1, 2, 4 and 9 years, respectively. The echocardiographic score (p < 0.001), NYHA class (p=0.008) and postprocedural mitral valve area (p=0.009) were significant independent predictors of intermediate long-term outcome.

CONCLUSIONS

Multicenter experience indicates that RNBMV is a safe and effective technique for the treatment of symptomatic mitral stenosis. As with the transseptal approach, patients with favorable mitral valve anatomy derive the greatest immediate and intermediate long-term benefit from this procedure.

Effects of pulmonary balloon valvuloplasty on right coronary artery blood flow in pulmonary valve stenosis

Pulmonary balloon valvuloplasty results in improvement in the right coronary artery blood flow velocity pattern and the volumetric flow in patients with pulmonary valve stenosis. These changes are closely related to concomitant changes in right ventricular systolic pressure.

Exercise-induced ST-segment variability may discriminate false positive tests

The clinical value of exercise-induced variations in ST-segment depression and R wave amplitude in consecutive sinus beats was studied in 160 patients who had a positive treadmill exercise test with the Bruce protocol. The patients, all of whom underwent cardiac catheterization, included 100 with coronary artery disease (CAD) (group with true positive test) and 60 with normal coronary arteries (group with false positive test). Minimal or no exercise-induced variations in the magnitude of ST-segment depression despite variations in R wave amplitude were observed in 84 of the 100 patients with CAD and in only 9 of the 60 patients with normal coronary arteries (P < .0001). Significant exercise-induced variations in ST-segment depression were observed in only 16 of 100 patients with CAD and in 51 of 60 patients with normal coronary arteries (P < .0001). The coefficient of variation of R wave amplitude was similar in both groups (no statistical significance), while the coefficient of variation of ST-segment depression was much greater in the patients with normal coronary arteries than in those with CAD (P < .0001). It is concluded that variability of ST-segment depression at peak exercise may discriminate false positive from the true positive exercise tests, improving the diagnostic ability of the method.

Significance of blood pressure levels achieved with felodipine anti-hypertensive treatment on cardiovascular structure and function changes

One of the targets of anti-hypertensive treatment is cardiovascular structural and functional improvements, while the level of blood pressure (BP) under treatment is related to patient morbidity and mortality. The aim of this study was to evaluate the relation of BP achieved after felodipine monotherapy to the degree of cardiovascular changes. Six hundred patients with essential hypertension were studied and grouped according to diastolic BP (DBP) levels after 6 months of therapy: 90-94 (n = 86), 85-89 (n = 186), 80-84 (n = 180) and < 80 mm Hg (n = 148). Overall BP fell from 175/103 to 137/83 mm Hg with a concomitant moderate reflex tachycardia (3.3%). Left ventricular (LV) dimensions decreased to a degree (-0.4 and -0.8%, P < 0.0001), with the greatest decrease in patients with lower DBP levels under treatment (P < 0.0001). LV systolic function improved to a modest degree (0.8%, P < 0.0001), depending on DBP fall (P < 0.0001), as did cardiac output (2.4%, P < 0.0001). LV systolic wall stress and total peripheral resistance fell (-18% and -14%, P < 0.0001) in relation to DBP drop (P < 0.0001), as did aortic root distensibility (55%, P < 0.0001). It is concluded that the degree of cardiovascular structure and function improvements are directly related to the DBP levels achieved under felodipine anti-hypertensive therapy.

Simple electrocardiographic markers for the prediction of paroxysmal idiopathic atrial fibrillation

BACKGROUND

The prolongation of intraatrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses are well known electrophysiologic characteristics in patients with paroxysmal atrial fibrillation (PAF).

METHODS

To search for possible electrocardiographic markers that could serve as predictors of idiopathic PAF, we measured the maximum P-wave duration (P maximum) and the difference between the maximum and the minimum P-wave duration (P dispersion) from the 12-lead surface electrocardiogram of 60 patients with a history of idiopathic PAF and 40 age-matched healthy control subjects.

RESULTS

P maximum and P dispersion were found to be significantly higher in patients with idiopathic PAF than in control subjects. A P maximum value of 110 msec and a P dispersion value of 40 msec separated patients from control subjects, with a sensitivity of 88% and 83% and a specificity of 75% and 85%, respectively.

CONCLUSIONS

P maximum and P dispersion are simple electrocardiographic markers that could be used for the prediction of idiopathic PAF.

Left atrial mechanical adaptation to long-standing hemodynamic loads based on pressure-volume relations

Left atrial (LA) adaptation during the development of left ventricular (LV) dysfunction is not fully understood. We performed echocardiographic assessment of LA volumes simultaneously with recordings of pulmonary wedge pressures in 60 patients. Twenty patients had no structural or functional LV abnormalities, 20 had a recent myocardial infarction with LV dysfunction, and 20 suffered from congestive heart failure (CHF). Pressure-volume loops were obtained at baseline and during increases in LA pressure produced by normal saline infusion. LA afterload was estimated by the effective LV elastance (E(LV)). Atrioventricular coupling was calculated by the E(LV)/E(es) ratio (where E(es) is the end-systolic elastance). E(es) increased in patients with myocardial infarction (0.80 +/- 0.09 mm Hg/ml, p <0.001), whereas it decreased in patients with CHF (0.22 +/- 0.05 mm Hg/ml, p <0.001) compared with controls (0.61 +/- 0.07 mm Hg/ml). Similarly, stroke workload increased in patients with myocardial infarction (60.7 +/- 7.3 mm Hg x ml, p <0.001), whereas it decreased in patients with CHF (25.4 +/- 2.2 mm Hg x ml, p <0.001) compared with controls (44.8 +/- 5.5 mm Hg x ml). In all patients LA stiffness (slope of the relation of the filling portion of the pressure-volume loop) was increased compared with controls (controls: 0.13 +/- 0.04, patients with myocardial infarction: 0.22 +/- 0.05, and patients with CHF: 0.27 +/- 0.05 mm Hg/ml, p <0.001 for both comparisons). Moreover, the E(LV)/E(es) ratio increased gradually as LV function deteriorated (controls: 1.06 +/- 0.10, patients with myocardial infarction: 1.35 +/- 0.16, and patients with CHF: 6.90 +/- 0.84, p <0.001). Thus, early in heart failure, LA pump function is augmented but LA stiffness increases and work mismatch occurs. With further progression of LV dysfunction, LA pump function decreases as a result of increased afterload imposed on the LA myocardium.

Reliability of the exercise-induced ST-segment changes to detect restenosis three months after coronary angioplasty: significance of the appearance in other leads

BACKGROUND

Exercise-induced ST-segment changes 3 months after angioplasty may sometimes show a false-positive result.

METHODS

We therefore analyzed the ST changes observed during the exercise tests performed before and 3 months after angioplasty in 118 patients with single-vessel coronary artery disease.

RESULTS

Ninety-two (78%) of the 118 patients had ST changes in the same lead before and after angioplasty, whereas the remaining 26 (22%) patients had ST changes in other leads in the postangioplasty test when compared with the preangioplasty exercise test. Restenosis was found in 44 (48%) of the 92 patients with ST changes in the some lead but in only four (15%) of the 26 patients with ST changes in other leads.

CONCLUSIONS

Exercise-induced ST-segment changes are not reliable markers of restenosis 3 months after angioplasty. ST-segment changes observed in other leads after angioplasty compared with the preangioplasty exercise test may show a false-positive result.

Reliability of exercise-induced ST segment changes to detect restenosis 3 months after coronary angioplasty: significance of the appearance in other leads

Exercise-induced ST-segment changes 3 months after angioplasty sometimes may show a false-positive result. We therefore analyzed the ST changes observed during the exercise tests performed before and 3 months after angioplasty in 118 patients with single-vessel coronary artery disease. Ninety-two (78%) of the 118 patients had ST changes in the same lead before and after angioplasty, whereas the remaining 26 (22%) patients had ST changes in other leads in the postangioplasty exercise test when compared with the preangioplasty test. Restenosis was found in 44 (48%) of the 92 patients with ST changes in the same lead but in only 4 (15%) of the 26 patients with ST changes in other leads. We conclude that exercise-induced ST segment changes are not reliable markers of restenosis 3 months after angioplasty. ST segment changes observed in other leads after angioplasty may show a false-positive result when compared with the preangioplasty exercise test.

Changes in phasic coronary blood flow velocity profile and relative coronary flow reserve in patients with hypertrophic obstructive cardiomyopathy

BACKGROUND

In this study, we both investigated coronary flow velocity in hypertrophic obstructive cardiomyopathy (HOCM) and tested the hypothesis of differing coronary flow reserve (CFR) of coronary arteries perfusing left ventricular regions with nonuniform myocardial hypertrophy by measuring the relative CFR.

METHODS AND RESULTS

Coronary flow velocity was assessed in left anterior descending coronary (LAD) and left circumflex (LCX) arteries in 18 patients with HOCM and marked hypertrophy only in the ventricular septum, in 13 patients without obstruction (HCM), and in 9 age- and sex-matched normal subjects at rest, during rapid atrial pacing, and after dobutamine infusion (5 to 30 microg/kg per minute). Relative CFR was estimated as the ratio between absolute CFR of the LAD and absolute CFR of the LCX (LAD/LCX(CF)). At the peak of rapid atrial pacing and during dobutamine stress, LAD/LCX(CF) was reversed in HOCM patients (from 1.25+/-0.11 to 0.82+/-0.07 and 0.79+/-0.06, respectively), whereas it remained unchanged in control subjects (from 1.0+/-0.1 to 1.0+/-0.05 and 1.0+/-0.05, respectively; P<.001). In HCM patients, LAD/LCX(CF) at rest was 1.10+/-0.11, whereas during rapid atrial pacing and dobutamine stress, it was 0.92+/-0.08 and 0.90+/-0.09, respectively. Relative CFR was 0.62+/-0.05 in HOCM patients and 1.05+/-0.05 (P<.001) in normal subjects. There was an inverse correlation between relative CFR and peak systolic outflow tract gradient (r2=.74, P<.001).

CONCLUSIONS

Regional distribution of hypertrophy in some patients with HOCM resulted in regional impairment of coronary flow. Relative CFR can be used to estimate regional disturbances of coronary flow and may help in patient selection for new interventional therapeutic techniques.

Assessment of accuracy of the Doppler pressure half-time method in the estimation of the mitral valve area immediately after balloon mitral valvuloplasty

AIM

The reliability of Doppler echocardiography in determining the mitral valve area after balloon mitral valvuloplasty has been questioned, as discrepancies were noted between measurements obtained by the pressure half-time method and those derived haemodynamically, immediately following completion of the procedure. Recent investigations, however, have indicated that these discrepancies may be attributable to the over-estimation of the mitral valve area by haemodynamic measurements, caused by the presence of the iatrogenic atrial septal defect complicating transseptal catheterization. The aim of the present study was to further test this hypothesis.

METHODS AND RESULTS

Measurements of the mitral valve area by the Doppler pressure half-time method and the Gorlin formula were obtained and compared in 238 consecutive patients before and immediately after retrograde non-transseptal balloon mitral valvuloplasty, which does not involve puncture and/or dilatation of the inter-atrial septum. No significant difference was found between Doppler- and Gorlin-derived measurements, neither before (1.04 +/- 0.23 vs 1.03 +/- 0.23 cm2, P = ns) nor immediately after (2.14 +/- 0.47 vs 2.12 +/- 0.49 cm2, P = ns) valvuloplasty. Linear regression analysis demonstrated a high degree of correlation between Doppler and Gorlin measurements before (r = 0.778) and after (r = 0.886) the procedure. Good agreement was confirmed by the Bland-Altman method.

CONCLUSION

Doppler echocardiography yields accurate measurements of the mitral valve area immediately after retrograde non-transseptal balloon mitral valvuloplasty. This finding supports the hypothesis that the creation of an iatrogenic atrial septal defect during transseptal catheterization may contribute to the poor agreement between Doppler and Gorlin data after balloon mitral valvuloplasty.

Effects of antihypertensive therapy on left atrial function

OBJECTIVES

To investigate left atrial (LA) function as a reservoir, as a conduit and as a booster pump in essential hypertension (EH). LA volumes were echocardiographically measured in 28 untreated hypertensive patients and in 20 control subjects.

BACKGROUND

LA makes a large contribution in left ventricular filling, especially in patients with impaired diastolic function. LA function is fundamental in left ventricular filling in hypertensive patients as hypertension results in left ventricular diastolic dysfunction.

METHODS

Diagnosis of EH (blood pressure > 140/90 mm Hg) was based on three repeated readings of blood pressure (BP). Patients with myocardial infarction, cardiomyopathy, valvular or congenital heart disease were excluded. Doppler diastolic early (E) and late (A) velocity of mitral inflow were measured. The following indexes were calculated: left ventricular mass index (LVMI) using the Penn convention; left ventricular stroke volume (LVSV); LA reservoir volume (LARV = LA maximal volume at mitral valve opening minus minimal volume); LA conduit volume (LACV = LVSV-LARV). Atrial systolic function was assessed by calculating the active emptying fraction (volume at onset of atrial systole minus minimal volume/volume at onset of atrial systole, the E/A ratio and the LA ejection force (0.5 rho A2 MOA, where rho = the density of blood, MOA = mitral orifice area from the parasternal short axis view). Measurements were obtained in all hypertensive patients before and after 16 weeks administration of either enalapril (10 or 20 mg) or enalapril +/- chlorthalidone (20/25 mg) once a day.

RESULTS

After 16 weeks of treatment, BP was reduced significantly (from 172/110 to 137/86 mm Hg, P < 0.001). LVMI decreased significantly as well (from 141 to 123 g/m2) although it was higher compared to controls (94 g/m2, P < 0.001). LARV decreased significantly (from 35.4 to 29.3 cm3, P < 0.05) while LACV increased significantly (from 43.8 to 51.3 cm3, P < 0.05), LA active emptying fraction and E/A ratio did not change. LA ejection force decreased significantly (from 20.9 to 18.1 kdynes, P < 0.05) but it was greater than controls (16.7 kdynes, P < 0.01). There was a positive relationship of LVMI to LARV (P < 0.01) in controls (r = 0.77) which held true in hypertensive patients, before (r = 0.72) and after treatment (r = 0.69). There was a negative relationship of LVMI to LACV (P < 0.01) in controls (r = -0.65), and in hypertensive patients untreated (r = -0.74) and after treatment (r = -0.72).

CONCLUSIONS

Our results showed that in hypertensive patients, LA reservoir function increases and LA conduit function decreases, while LA ejection force increases. Antihypertensive treatment with enalapril and/or thiazide, induces normalisation of the LA function in parallel to left ventricular hypertrophy regression.

Effects of menopause on aortic root function in hypertensive women

OBJECTIVES

This study sought to determine whether the natural decrease in sex hormones that occurs during menopause in hypertensive women plays a role in aortic root stiffness.

BACKGROUND

The effect of menopause-induced sex hormone deprivation on aortic root function is not known; however, it is of special interest in hypertensive subjects, whose aortic elastic properties are already compromized.

METHODS

Eighteen women with essential hypertension were followed-up for 3 years, during which time they went through menopause (group A) and were compared with 22 age-matched hypertensive women with normal menses (group B) and 20 hypertensive men (group C). Blind echocardiographic tracings and simultaneous blood pressure measurements were obtained after at least 30 medication-free days, both at baseline and 3.5 years later.

RESULTS

Aortic root function tended to be aggravated in both groups B and C, but not significantly so, with no between-group differences (p = NS), whereas it deteriorated in group A. Thus, in menopausal hypertensive subjects, aortic root systolodiastolic percent change decreased (from 6.7% to 4.9%, p < 0.0001 [p = 0.002 vs. group B; p = 0.006 vs. group C]); cross-sectional compliance decreased (from 18 to 13 cm2/mm Hg, p < 0.0001 [p = 0.002 vs. group B; p = 0.03 vs. group C]); Peterson's elastic modulus increased (from 1.2 to 1.9 dynes/cm2, p = 0.0006 [p = 0.003 vs. group B; p = 0.005 vs. group C]); aortic stiffiness index increased (from 7.0 to 10.8, p = 0.0008 [p = 0.004 vs. group B; p = 0.007 vs. group C]); and aortic root distensibility decreased (from 1.8 to 1.2 dynes/cm2, p < 0.0001 [p = 0.0003 vs. group B; p = 0.007 vs. group C]). Serum lipids did not change significantly in any group (p = NS).

CONCLUSIONS

In hypertensive women, the effect of menopause on the elastic properties of the aortic root is abrupt and devastating.

Arterial blood pressure changes in children and adolescents with insulin-dependent diabetes mellitus

Diabetic nephropathy may develop in childhood and is often related to hypertension. The 24-hour ambulatory blood pressures were measured in 63 children with insulin-dependent diabetes mellitus and were compared with those of 54 healthy siblings. The patients were without clinical complications. The 24-hour recording of their blood pressures revealed higher 24-hour systolic blood pressure (SBP) (115.8 +/- 8.2), 24-hour diastolic blood pressure (DBP) (67.5 +/- 4.6), 24-hour mean arterial pressure (MAP) (81.8 +/- 5.2) compared with control subjects: 24-hour SBP (112.7 +/- 6.7), 24-hour DBP (64.7 +/- 4.1), 24-hour MAP (78.9 +/- 4.5) (p = 0.03, p = 0.001, p = 0.002, respectively). Of the daytime blood pressures, SBP, DBP, MAP were also higher (117.7 +/- 8.7, 69.7 +/- 5.2, 83.8 +/- 5.8) compared with those of siblings (114.9 +/- 6.9, 67.3 +/- 4.3, 81.1 +/- 4.9) (p = 0.05, p = 0.009, p = 0.008, respectively). Of the nighttime blood pressures, SBP, DBP, MAP were higher in patients (108.7 +/- 8.9, 59.5 +/- 6.9, 74.6 +/- 6.9) compared with control subjects (104.8 +/- 7.0, 55.1 +/- 5.0, 70.5 +/- 5.1) (p = 0.01, p = 0.0002, p = 0.0006, respectively). Furthermore, the blood pressure burden was evaluated. Blood pressure burden was defined as the percentage of the increased blood pressure readings greater than the 95th percentile divided by the total number of recorded blood pressures during a corresponding period. Patients had a 43% higher 24-hour SBP burden (19.6 +/- 16.5) and a 50% higher 24-hour DBP burden (12.3 +/- 9.6) in relation to that of control subjects (13.7 +/- 12.8, 8.3 +/- 12.3) (p = 0.03, p = 0.009, respectively). The SBP burden (17.9 +/- 14.6) and DBP burden (11.5 +/- 9.2) of the day was approximately 50% higher in the patients in the relation to control subjects (11.9 +/- 11.1, 7.8 +/- 6.7) (p = 0.01, p = 0.01, respectively). Therefore it seems that hemodynamic changes may appear early in children with diabetes.

Modification of ventricular tachycardia by carotid sinus massage

A case of ventricular tachycardia (VT) was aggravated by carotid sinus massage in a woman with an old myocardial infarction. The patient presented with a wide QRS complex tachycardia with a rate of 143 beats/min, which fulfilled the classic and newer electrocardiographic criteria for the diagnosis of VT. Carotid sinus massage performed during the tachycardia resulted in its conversion to another, wide QRS complex tachycardia, with different morphology and a faster rate resembling ventricular flutter. This latter tachycardia was converted to sinus rhythm by a thump on the patient's chest. The initial tachycardia was proved to be of ventricular origin by electrophysiologic study at a later stage during a recurrence. Vagal stimulation probably resulted in inhomogeneous increase of the ventricular refractory period, creating conditions for a reentrant circuit other than the preexisting one and for the emergence of VT with a different QRS morphology and rate. Although termination and/or initiation of VT by carotid sinus massage has been reported in the past, modification of VT by carotid sinus massage has not been described previously.

Assessment of time domain and spectral components of heart rate variability immediately before ischemic ST segment depression episodes

In an attempt to study autonomic function during the 5-minute period preceding ischemic ST segment depression (decreases ST) episodes, we selected 138 decreases ST episodes, without preceding decreases ST during the last 15 minutes before each episode, from the Holter tapes of 35 patients with multivessel coronary artery disease. For the 5-minute period preceding each decreases ST episode, we calculated the following heart rate variability (HRV) indices; the mean RR interval (RR5), the standard deviation of all RR intervals (SD Index5), the corresponding coefficient of variation (CV5), and the natural log (Ln) of the spectral components, total power at 0.000 to 0.400 Hz (TP5), low frequency power at 0.040 to 0.150 Hz (LF5), high frequency power at 0.150 to 0.400 Hz (HF5), and the ratio of the low to high frequency power (LF5/HF5). As HRV indices of the 24-hour period, we calculated the respective RR, SD Index, CV, LnTP, LnLF, LnHF, and Ln LF/HF. RR5, SD Index5, CV5, and Ln TP5 were all significantly lower than RR (t = -5.343, p = 3.7 x 10(-7)), SD Index (t = -19.091, p = 1.99 x 10(-40)), CV (t = -15.780, p = 1.28 x 10(-32)), and LnTP (t = -3.210, p = 0.0016), respectively. LnHF5 was inversely correlated with the magnitude of the decreases ST; r = -0.174, P < 0.05, and CV5 was inversely correlated with the natural log (Ln) of the ischemic event duration; r = -0.183, P < 0.05. Analogous results were obtained for both the painful and silent decreases ST episodes. It is concluded that HRV is decreased during the 5-minute period preceding decreases ST episodes, and is inversely related with the magnitude and the duration of the *ST.

Changes in phasic coronary blood flow velocity profile in relation to changes in hemodynamic parameters during stress in patients with aortic valve stenosis

BACKGROUND

Alterations in phasic coronary flow profile have been demonstrated at rest in patients with aortic valve stenosis (AVS) but have never been studied under conditions of hemodynamic stress.

METHODS AND RESULTS

Thirty-four patients with significant pure AVS (21 with exertional symptoms [group 1], 13 asymptomatic [group 2]) and 9 control subjects (group 3), all with normal coronary arteries, were studied successively at rest, during rapid atrial pacing, and after dobutamine infusion (5 to 30 micrograms.kg-1.min-1 i.v.) by proximal left anterior descending (LAD) intracoronary Doppler flow velocimetry concomitant with hemodynamic measurements. Systolic retrograde coronary flow velocity (CFV) was recorded only in patients with AVS, and its resting peak value was positively correlated with peak aortic pressure gradient (APG) (r = .63, P < .001). In group 1, there was lower aortic valve area (0.58 +/- 0.10 versus 0.75 +/- 0.08 cm2, P < .001) and higher resting APG and peak systolic retrograde CFV than in group 2, and also higher resting peak diastolic and mean CFV than in groups 2 and 3. In the two AVS groups, there were no changes from rest in APG and retrograde CFV at peak pacing rate; however, these parameters increased concomitantly and significantly at peak dobutamine stress. The ratio of the resting systolic to diastolic CFV curve area was inversely correlated with mean APG (r = -.54, P < .001); it was significantly lower in group 1 than in groups 2 and 3 (0.19 +/- 0.07 versus 0.29 +/- 0.10 and 0.30 +/- 0.04, respectively, both P < .005) and increased at peak pacing (group 1, to 0.29 +/- 0.14; group 2, to 0.39 +/- 0.12; group 3, to 0.38 +/- 0.07; all P < .001). At peak dobutamine stress, it decreased in patients with AVS (group 1, to 0.05 +/- 0.05; group 2, to 0.08 +/- 0.03; both P < .001) but did not change in group 3 (0.25 +/- 0.05). From rest to peak dobutamine stress, in both AVS groups there was increased retrograde systolic (group 1, 441 +/- 483%; group 2, 681 +/- 356%; both P < .001), decreased total systolic (group 1, -66 +/- 25%, P < .001; group 2, -19 +/- 24%; P = NS), and increased diastolic (group 1, 33.4 +/- 31.7%; group 2, 197.7 +/- 105.1%; both P < .001; group 1 versus group 2, P < .001) CFV curve area. In contrast, group 3 showed comparable increases in both systolic (143.5 +/- 44.4%) and diastolic (197.1 +/- 75.2%) CFV area (both P < .001). The stress-induced increases in the mean CFV and blood flow exceeded or were comparable with the concomitant increases in the estimated myocardial metabolic demand in groups 2 and 3 but were significantly lower in group 1.

CONCLUSIONS

Stress-induced changes in LAD phasic CFV profile differ significantly between patients with and without AVS. In AVS, these changes are closely related to the concomitant stress-induced changes in hemodynamic parameters.

Effects of atrial, ventricular, and atrioventricular sequential pacing on coronary flow reserve

Experimental animal data have indicated that altered left ventricular depolarization sequence as a result of right ventricular pacing may diminish coronary blood flow in the distribution of the left anterior descending coronary artery. To further investigate this, we compared the effects of atrial, ventricular, and atrioventricular (AV) sequential pacing on coronary flow reserve. Twenty-seven patients (24 male, mean age 55 +/- 7 years) with normal left anterior descending coronary arteries were studied. Coronary flow reserve was calculated as the ratio of mean flow velocity at maximal coronary vasodilatation to mean flow velocity at baseline. The study consisted of two parts. In the first part, AV sequential pacing was compared to atrial pacing at the same rate; coronary flow reserve did not differ significantly between the two pacing modes (14 patients, 4.85 +/- 1.88 vs 5.47 +/- 1.55, respectively, P > 0.05). In the second part, all three pacing modalities were compared; coronary flow reserve was significantly higher during ventricular compared to AV sequential pacing, but not significantly different compared to atrial pacing (3.69 +/- 1.42 vs 2.90 +/- 0.86 vs 3.11 +/- 0.89, respectively, P < 0.05). This difference was secondary to a significant decrease in mean baseline velocity during ventricular pacing, while mean velocity during hyperemia was comparable between the three pacing modes. It is concluded that AV sequential pacing does not appear to exert a significant effect on coronary flow reserve. Ventricular pacing, however, may lower resting coronary blood velocity in some patients, without affecting maximal coronary blood velocity, resulting in a higher coronary flow reserve.

Myocardial trophic effects of blood pressure in children with insulin-dependent diabetes mellitus

To evaluate the effect of blood pressure (BP) on the left ventricular mass index (LVMI), 66 children with IDDM 13 +/- 3 years of age were studied and compared with 58 healthy age-matched siblings. The 24 h BP recordings disclosed that children with diabetes had higher DBP (68 vs. 65 mm Hg, P = 0.002), especially at night (60 vs. 55 mm Hg, P = 0.00007), with a minimisation of the normal nocturnal hypotension (-9.9 vs. -12.4 mm Hg, P = 0.04). Their LVMI was higher (79 vs. 71 g/m2, P = 0.02); it was independent of BP values and variability (P = NS), but it was positively correlated with heart rate (r = -0.46, P = 0.0005). In the control group, LVMI was significantly correlated with the mean SBP (r = 0.46, P = 0.0005); with its variability (r = 0.32, P = 0.02) and, to a lower extent, with heart rate (r = -0.29, P = 0.03). It is concluded that in children with diabetes mellitus the participation of BP in myocardial hypertrophy is not so obvious, although the BP load is increased. The increase of the LVMI occurs early in life and before the onset of hypertension.

Acute effect of captopril administration on baroreflex sensitivity in patients with acute myocardial infarction

Depressed baroreflex sensitivity (BRS) after acute myocardial infarction (AMI) is considered an indication of decreased vagal and/or increased sympathetic tone. To determine the effect of angiotensin converting enzyme inhibitors (ACEI) on BRS after AMI we studied 27 patients with a first Q wave AMI, no signs of heart failure and no history of arterial hypertension or diabetes mellitus. An additional group of 10 patients with the same clinical characteristics served as controls. On the 5th day after the onset of AMI, three consecutive boluses of phenylephrine were given intravenously and baseline BRS was taken as the mean slope of the linear regression lines of RR intervals over systolic blood pressure. QT interval was also measured and corrected according to Bazett's formula (QTc). Consequently, a single oral dose of captopril 50 mg or placebo was given to treatment or control group patients, respectively; BRS and QTc were reassessed 1 h later. One hour after captopril administration BRS increased from 5.95 +/- 2.80 to 9.14 +/- 3.46 ms.mmHg-1 (P < 0.0001); QTc increased from 414 +/- 46 to 425 +/- 46 ms (P < 0.0001), systolic blood pressure decreased from 125 +/- 19 to 115 +/- 15 mmHg (P = 0.0002), while heart rate did not change significantly. Baseline BRS was correlated only with age (r = -0.74, P < 0.0001). In the control group, 1 h after placebo, no difference was observed in any variable compared to baseline. Captopril appears to improve BRS immediately in the early phase of AMI.

Left ventricular and aortic root structure and function changes with beta blocker antihypertensive therapy. A one-year double blind study of celiprolol and metoprolol

Using echocardiographic and Doppler methodology, we evaluated the effects of celiprolol 200-400 mg/day and metoprolol 100-200 mg/day, given for one year, on haemodynamics, left ventricular structure and function, and aortic root distensibility in 40 hypertensive patients. Total peripheral resistance was unchanged with metoprolol (-1.7%) but decreased with celiprolol (-11.2%), a significant difference between the two treatments (P = 0.01). Left ventricular mass index was reduced by 5.7% in those patients receiving metoprolol and by 11.8% in those receiving celiprolol (P < 0.001). Cardiac index fell significantly with metoprolol and marginally with celiprolol (-13.9% vs. 5.9%, P = 0.003). Left ventricular diastolic function-as shown by the transmitral early to late peak filling velocity ratio-was not altered with metoprolol, but a significant increase (17%, P = 0.2) was seen with celiprolol. Both metoprolol and celiprolol increased aortic root distensibility, with celiprolol having a significantly greater effect (80% vs. 30%, P < 0.01). We conclude that, in comparison to metoprolol, long term antihypertensive therapy with celiprolol improves left ventricular diastolic and aortic root function, whilst reducing total peripheral resistance and left ventricular hypertrophy.