Respiratory symptoms and chronic bronchitis in people with and without HIV infection

OBJECTIVES

High rates of respiratory symptoms and chronic bronchitis (CB) are reported in people with HIV infection (PWH). We investigated the prevalence of respiratory symptoms and CB in PWH and HIV-negative people in the Pharmacokinetic and clinical Observations in PeoPle over fiftY (POPPY) study.

METHODS

Assessment of respiratory symptoms and CB was undertaken using the modified form of the St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease (COPD). Univariate (χ² tests, Mann-Whitney U tests and Spearman's rank correlation) and multivariable (linear and logistic regression) analyses were performed to consider associations of respiratory symptoms with demographic, lifestyle and HIV-related parameters, and with depressive symptoms and quality of life.

RESULTS

Among the 619 participants, respiratory Symptom scores were higher in older and younger PWH compared to older HIV-negative people, with median (interquartile range) scores of 17.7 (6.2, 39.5), 17.5 (0.9, 30.0) and 9.0 (0.9, 17.5), respectively (P = 0.0001); these differences remained significant after confounder adjustment. Sixty-three participants (10.2%) met the criteria for CB [44 (14.0%) older PWH, 14 (9.2%) younger PWH, and five (3.3%) older HIV-negative people; P = 0.002], with these differences also remaining after adjustment for confounding variables, particularly smoking status [older vs. younger PWH: odds ratio (OR) 4.48 (95% confidence interval (CI) 1.64, 12.30); P = 0.004; older PWH vs. HIV-negative people: OR 4.53 (95% CI 1.12, 18.28); P = 0.03]. Respiratory symptoms and CB were both associated with greater depressive symptom scores and poorer quality of life. No strong associations were reported between CB and immune function, HIV RNA or previous diagnosis of any AIDS event.

CONCLUSIONS

Respiratory symptoms and CB are more common in PWH than in demographically and lifestyle-similar HIV-negative people and are associated with poorer mental health and quality of life.

Investigation of the safety and feasibility of AAV1/SERCA2a gene transfer in patients with chronic heart failure supported with a left ventricular assist device - the SERCA-LVAD TRIAL

The SERCA-LVAD trial was a phase 2a trial assessing the safety and feasibility of delivering an adeno-associated vector 1 carrying the cardiac isoform of the sarcoplasmic reticulum calcium ATPase (AAV1/SERCA2a) to adult chronic heart failure patients implanted with a left ventricular assist device. The SERCA-LVAD trial was one of a program of AAV1/SERCA2a cardiac gene therapy trials including CUPID1, CUPID 2 and AGENT trials. Enroled subjects were randomised to receive a single intracoronary infusion of 1 × 10¹³ DNase-resistant AAV1/SERCA2a particles or a placebo solution in a double-blinded design, stratified by presence of neutralising antibodies to AAV. Elective endomyocardial biopsy was performed at 6 months unless the subject had undergone cardiac transplantation, with myocardial samples assessed for the presence of exogenous viral DNA from the treatment vector. Safety assessments including ELISPOT were serially performed. Although designed as a 24 subject trial, recruitment was stopped after five subjects had been randomised and received infusion due to the neutral result from the CUPID 2 trial. Here we describe the results from the 5 patients at 3 years follow up, which confirmed that viral DNA was delivered to the failing human heart in 2 patients receiving gene therapy with vector detectable at follow up endomyocardial biopsy or cardiac transplantation. Absolute levels of detectable transgene DNA were low, and no functional benefit was observed. There were no safety concerns in this small cohort. This trial identified some of the challenges of performing gene therapy trials in this LVAD patient cohort which may help guide future trial design.

Factors associated with obesity in the Pharmacokinetic and Clinical Observations in People over Fifty (POPPY) cohort: an observational cross-sectional analysis

OBJECTIVES

The aims of the study were to describe the prevalence of obesity in the Pharmacokinetic and Clinical Observations in People over Fifty (POPPY) cohort, to identify demographic, clinical and HIV-specific factors associated with obesity, and to characterize the association between obesity and sociodemographic, clinical and HIV-specific factors and quality of life (QoL).

METHODS

A cross-sectional analysis was carried out of baseline data from the three groups ["older" people with HIV infection (PWH) aged ≥ 50 years, "younger" PWH aged < 50 years and HIV-negative controls aged ≥ 50 years] within the POPPY cohort. Obesity was defined as a body mass index (BMI) > 30 kg/m² .

RESULTS

A total of 1361 subjects were included in the study, of whom 335 (24.6%) were obese. The prevalence of obesity was higher in controls (22.3%) than in older (16.8%) and younger (14.2%) PWH, with no differences between the two groups of PWH. Factors associated with obesity were older age, female gender, black African ethnicity and alcohol consumption. Recreational drug use and a higher current CD4 T-cell count (in PWH) were associated with lower and higher odds of being obese, respectively. The presence of obesity was associated with worse physical health QoL scores, higher odds of having cardiovascular disease, type 2 diabetes and hypertension, but lower odds of having osteopenia/osteoporosis, irrespective of HIV status.

CONCLUSIONS

Despite a lower prevalence of obesity in PWH, specific subgroups (women, people of black African origin and older people) were more likely to be obese, and negative health consequences of obesity were evident, regardless of HIV status. Whether targeted preventive strategies can reduce the burden of obesity and its complications in PWH remains to be determined.

Study on the admission levels of circulating cell-free DNA in patients with acute myocardial infarction using different quantification methods

Circulating cell-free DNA (cf-DNA) is present in human biological fluids, mainly in plasma and serum, originating from cell death, a process that massively takes place during acute myocardial infarction (AMI). In the present study, cf-DNA was assessed by different quantification techniques, in order to determine its levels in patients admitted with AMI. A total of 130 subjects were included in the study: 80 ST elevation myocardial infarction (STEMI) patients and 50 healthy controls. Cf-DNA extracted from plasma was analyzed by: a) Qubit 3.0 with single (ss) and double (ds) stranded DNA assay kits, b) NanoDrop and c) quantitative PCR (qPCR). Cf-DNA levels were recorded elevated in AMI patients compared to those of healthy individuals. Specifically, Qubit 3.0 ss-DNA kit provided the highest cf-DNA concentration values for all the samples analyzed in comparison with ds-DNA assay kit and NanoDrop, approaching the values obtained by qPCR. Cf-DNA augments in massive cell death settings, including AMI, proposing that the quantification of its levels by novel methodologies could contribute to patient diagnosis and clinical management.

miRNA polymorphisms and risk of premature coronary artery disease

OBJECTIVE

Several microRNA (miRNA) polymorphisms have been associated with susceptibility to specific health disorders, including cardiovascular diseases. The aim of the present study was to investigate whether four well-studied miRNA polymorphisms in non-Caucasian populations, namely miR146a G>C (rs2910164), miR149 C>T (rs2292832), miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444), contribute to the risk for the development of premature Coronary Artery Disease (CAD) in the Greek population.

METHODS

We used a case-control study to examine these associations in 400 individuals: 200 CAD patients [including a subgroup of myocardial infraction (MI) patients] and 200 healthy controls, all of Greek origin. MiRNA polymorphisms were genotyped using three different assays: Polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP), High resolution Melting (HRM) and Sanger sequencing.

RESULTS

Two of these polymorphisms, miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444) were found to be strongly associated with increased risk for CAD (p=0.0388 and p=0.0013, respectively) and for MI (p=0.0281 and p=0.0273, respectively). Furthermore, miR146C-miR149C-miR196T-miR499G allele combination appeared to be significantly related to CAD (p=0.0185) and MI (p=0.0337) prevalence.

CONCLUSIONS

Our results suggest that at least two of the studied polymorphisms, miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444), as well as the miR146C-miR149C-miR196T-miR499G allele combination could represent useful biomarkers of CAD and/or MI susceptibility in the Greek population. These special genetic characteristics, in combination with environmental factors and personal habits, might contribute to CAD and/or MI prevalence.

Level of agreement between frequently used cardiovascular risk calculators in people living with HIV

OBJECTIVES

The aim of the study was to describe agreement between the QRISK2, Framingham and Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) cardiovascular disease (CVD) risk calculators in a large UK study of people living with HIV (PLWH).

METHODS

PLWH enrolled in the Pharmacokinetic and Clinical Observations in People over Fifty (POPPY) study without a prior CVD event were included in this study. QRISK2, Framingham CVD and the full and reduced D:A:D CVD scores were calculated; participants were stratified into 'low' (< 10%), 'intermediate' (10-20%) and 'high' (> 20%) categories for each. Agreement between scores was assessed using weighted kappas and Bland-Altman plots.

RESULTS

The 730 included participants were predominantly male (636; 87.1%) and of white ethnicity (645; 88.5%), with a median age of 53 [interquartile range (IQR) 49-59] years. The median calculated 10-year CVD risk was 11.9% (IQR 6.8-18.4%), 8.9% (IQR 4.6-15.0%), 8.5% (IQR 4.8-14.6%) and 6.9% (IQR 4.1-11.1%) when using the Framingham, QRISK2, and full and reduced D:A:D scores, respectively. Agreement between the different scores was generally moderate, with the highest level of agreement being between the Framingham and QRISK2 scores (weighted kappa = 0.65) but with most other kappa coefficients in the 0.50-0.60 range.

CONCLUSIONS

Estimates of predicted 10-year CVD risk obtained with commonly used CVD risk prediction tools demonstrate, in general, only moderate agreement among PLWH in the UK. While further validation with clinical endpoints is required, our findings suggest that care should be taken when interpreting any score alone.

Expression of miR-208b and miR-499 in Greek Patients with Acute Myocardial Infarction

BACKGROUND/AIM

Certain microRNAs (miRs) present in human plasma are candidate biomarkers for cardiovascular diseases, including acute myocardial infarction (AMI). We examined the expression of two cardiac-specific miRs (miR-208b and miR-499) in a Greek pathological population.

MATERIALS AND METHODS

Plasma samples from AMI patients and healthy subjects (controls) were analyzed using TaqMan® MicroRNA assays.

RESULTS

The concentration of both miRs was significantly elevated in AMI patients compared to healthy controls. Moreover, receiver-operating characteristic (ROC) curve analysis showed that miR-208b and miR-499 displayed similar properties with the established AMI biomarker cardiac troponin T (cTnT).

CONCLUSION

We showed, for the first time, that these miRs could be used as AMI biomarkers in our population as well. Our data are in agreement with those of studies based on different population groups and further strengthen the observation that plasma levels of circulating miR-208b and miR-499 could serve as potential AMI biomarkers.

Quality of Life at work and Motivation for Research Activities for Residents of General Practice in two Different Surgical Departments in Greece

Introduction

Quality of life at work has very much to do with educational efforts during medical residence years. Constant changes of work environment for general practice residents, is a strong reason for high levels of stress at work.

Objectives

Our study is to present the general rules of work for general practice residents in surgical departments in Greece and the quality of their lives and career motivation.

Methods

We use information coming from two hospitals, a large city hospital which covers a population of 780.000 of citizens during all-night duties, and a provincial hospital, which covers a population of 50.000 citizens.

Results

In both workplaces, general practice residents spend much of their education time in the emergencies department or the outpatient clinics of surgery. Stress is more intense in the large hospital, based on the number of patients examined per day and the frustration they receive at work. However, the heavy duty to accompany a patient for a transfer to other hospital is much more often in province, and then the stress is much more intense and lasting. Frustration is also often in the urban hospital where the residents of various specialties are more experienced and have more confidence due to their departments expertise. Satisfaction at work varies according to the personality of every doctor.

Conclusions

Opportunities for scientific development through participation in scientific meetings was stronger in the provincial Hospital due to a good team of strongly motivated researchers that happened to be there and better work environment.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Ineffective efforts in ICU assisted ventilation: Exploring causalities via multiscale analysis

Intensive Care Unit (ICU) is a data intensive environment, requiring continuous monitoring of patient's physiology and response to treatment. In assisted ventilation, where patient effort that triggers the ventilator and there is need for patient-ventilator coupling, attention is required in cases where patient's effort that doesn't trigger the ventilator at all. When synchronization between the patient's attempt to breath and the assisted ventilation event is lost, an ineffective effort (IE) event takes place. A series of relevant bioparameters continuously monitored, are meant to guide the medical professionals in appropriately adapting the operation and treatment, in order to minimize IEs. The purpose of this work is to investigate the causal relations between physiological or ventilation parameters and IE events. A multiscale approach is proposed, based on wavelet similarity and localized phase relationship. The proposed method indicates the existence of distinct frequency zones correlated with the IE experienced by the patient.

Multiparametric modeling of the ineffective efforts in assisted ventilation within an ICU

In the context of assisted ventilation in ICU, it is of vital importance to keep a high synchronization between the patient's attempt to breath and the assisted ventilation event, so that the patient receives the ventilation support requested. In this work, experimental equipment is employed, which allows for unobtrusive and continuous monitoring of a multiple relevant bioparameters. These are meant to guide the medical professionals in appropriately adapting the treatment and fine-tune the ventilation. However, synchronization phenomena of different origin (neurological, mechanical, ventilation parameters) may occur, which vary among patients, and during the course of monitoring of a single patient, the timely recognition of which is challenging even for experts. The dynamics and complex causal relations among bioparameters and the ventilation synchronization are not well studied. The purpose of this work is to elaborate on a methodology toward modeling the ventilation synchronization failures based on the evolution of monitored bioparameters. Principal component analysis is employed for the transformation into a small number of features and the investigation of repeating patterns and clusters within measurements. Using these features, nonlinear prediction models based on support vector machines regression are explored, in terms of what past knowledge is required and what is the future horizon that can be predicted. The proposed model shows good correlation (over 0.74) with the actual outputs, constituting an encouraging step toward understanding of ICU ventilation dynamic phenomena.

Effects of ranolazine on left ventricular diastolic and systolic function in patients with chronic coronary disease and stable angina

INTRODUCTION

The present study examined the effect of ranolazine, which acts via the mechanism of selective inhibition of late INa+, on parameters of left ventricular systolic and diastolic function in patients suffering from angiographically confirmed chronic coronary artery disease, presenting with chronic stable angina.

METHODS

We studied 40 patients (age 67 ± 9 years; 30 men, 10 women) with chronic coronary artery disease who reported angina symptoms on optimal medication and who were not suitable for invasive treatment. Patients were randomized to the ranolazine group (group A, 20 patients taking oral ranolazine 500 mg bid for 3 months) and the control group (group B, 20 patients who did not receive the drug). Left ventricular systolic and diastolic function was assessed echocardiographically at baseline and after the end of the three-month treatment period. Left ventricular ejection fraction by the modified Simpson's method, E and A left ventricular filling velocities, E/A ratio, deceleration time (DT) of E, isovolumic relaxation time (IVRT), E and A waves, and the E/E ratio were measured using 2-dimensional echocardiography, Doppler and tissue Doppler imaging (TDI).

RESULTS

Group A patients demonstrated a clear improvement of their initial angina symptoms. There were no adverse effects from ranolazine requiring withdrawal from the study. There was no statistically significant change in left ventricular systolic function in either group. A statistically significant change was seen in indexes of diastolic function measured using both conventional Doppler and TDI in Group A patients compared with Group B patients after three months' ranolazine treatment period. The changes in left ventricular diastolic function indexes in Group A patients were as follows: E 0.58 ± 0.11 vs. 0.76 ± 0.12 m/s, p<0.001; A 0.71 ± 0.22 vs. 0.83 ± 0.19 m/s, p<0.001; E/A 0.81 ± 0.14 vs. 0.97 ± 0.17, p<0.005; 5.4 ± 0.7 vs. 6.8 ± 0.9 cm/s, p<0.005; 7.2 ± 0.8 vs. 8.3 ± 1.1 cm/s, p<0.005; E/ 10.7 ± 1.1 vs. 11.1 ± 0.8, p=ns; DT 251 ± 14 vs. 226 ± 17 ms, p<0.004; IVRT 95 ± 11 vs. 74 ± 9 ms, p<0.001. Systolic function did not change: EF 46.3 ± 3.4 vs. 46.7 ± 2.7%, p: ns.

CONCLUSIONS

The use of ranolazine in patients suffering from chronic coronary artery disease has a favorable impact on diastolic function parameters. Accordingly, a clinical benefit could be observed due to an improvement in patients' symptoms.

Management of atrial fibrillation in Greece: the MANAGE-AF study

BACKGROUND

Although atrial fibrillation (AF) is a highly prevalent health problem with high morbidity and mortality, data regarding the clinical characteristics and management of AF in the Greek population are scarce. The "Current Clinical Practice in the MANAGEment of Atrial Fibrillation in Greece" study (MANAGEAF) aimed to assess the epidemiological features as well as the daily clinical practice in the management of Greek patients with AF.

METHODS

Taking into consideration the distribution of the Greek population, 603 consecutive patients over 18 years of age, with any type of AF, presenting at the emergency departments or outpatient clinics of 27 different centers, were included in our study.

RESULTS

The mean age of the patients was 68.5 ± 12.1 years, with male patients representing 52.5% of the study population. The most common AF type in our cohort was non-paroxysmal AF (60%), including the patients with permanent (24.1%), persistent (17.4%), long-standing (4.8%) and first diagnosed AF (13.8%). Hypertension was the most common comorbidity (70.3%). A history of stroke or transient ischemic attack was detected in 9.2% of the patients, while 6.2% had a history of gastrointestinal bleeding. About half of the patients (49.3%) were treated with anticoagulant drugs, mainly vitamin K antagonists (46.9%), while 34.2% were on antiplatelet drugs, aspirin and/or clopidogrel. The mean INR level (1.7 ± 0.8) was sub-therapeutic, although the mean values for CHADS2 and CHA2DS2-VASc scores were 1.6 ± 1.2 and 3.0 ± 1.7, respectively.

CONCLUSION

The MANAGE-AF baseline results indicate unsatisfactory levels of compliance with the current guidelines for the management of AF in Greece. Considering the undisputed effectiveness of anticoagulant treatment for preventing AF-related strokes, MANAGE-AF demonstrates the need for optimization of our therapeutic strategies for the management of cardioembolic stroke risk.

Unsuspected pulmonary embolism in patients with cancer

BACKGROUND

The natural history of unsuspected pulmonary embolism (PE) in patients with cancer has not been thoroughly studied.

METHODS

We used the RIETE Registry data to compare the clinical characteristics, treatment strategies and outcome in cancer patients with unsuspected PE and in those presenting with symptomatic, acute PE.

RESULTS

Up to December 2011, 78 cancer patients with unsuspected PE and 1,994 with symptomatic PE had been enrolled. Patients with unsuspected PE more likely had colorectal cancer than those with symptomatic PE (28% vs. 13%), and less likely had prostate (3.8% vs. 10%) or hematologic (1.3% vs. 6.4%) cancer, or prior venous thromboembolism (3.8% vs. 12%). While the patients were receiving anticoagulant therapy, the incidence of PE recurrences (0% vs. 1.9%) or major bleeding (2.6% vs. 4.8%) were similar. After completion of anticoagulation, recurrent PE developed in 2.6% vs. 1.4% of patients, and major bleeding in 0% vs. 0.4%, respectively.

CONCLUSIONS

Our findings suggest that the clinical characteristics and outcome in cancer patients with unsuspected PE are quite similar to those in patients with symptomatic PE.

Brain natriuretic peptide: a marker of cardiac dysfunction with ventricular or dual-chamber pacing

BACKGROUND/OBJECTIVES

The inability of trials to exhibit the superiority in survival of atrioventricular compared to ventricular pacing can be partially explained by the apical stimulation of the right ventricle, which adversely affects both short- and long-term ventricular performance. We evaluated the impact of pacing mode (DDDR vs. VVIR) on the brain natriuretic peptide (BNP) level in patients with sick-sinus syndrome (SSS).

METHODS

Sixty-seven patients were treated with DDDR pacemaker implantation due to SSS. They were randomized during the first post-implant day either to DDDR or WIR pacing mode and were reevaluated after 30 days. Group A comprised 35 patients on DDDR pacing mode and group B 32 patients on WIR pacing mode. Peripheral blood samples were drawn for BNP measurement at the time of randomization and one month later.

RESULTS

BNP levels increased significantly in both groups at 30 days (group A: 85.6 +/- 29.5 pg/ml to 107.2 +/- 34.6 pg/ml, group B: 82.7 +/- 27.6 pg/ml to 253.1 +/- 60.2 pg/ml). On day 30, BNP levels in group B were significantly higher than in group A (P < 0.0001).

CONCLUSIONS

Pacing from the apex of the right ventricle provokes an increase in the BNP levels regardless of the pacing mode. BNP is probably a very early marker predicting the structural and/or functional heart changes after long-term pacing from the apex of the right ventricle.

An isolated single L-I type coronary artery with severe LAD lesions treated by transradial PCI

Cases of coronary arteries with anomalous aortic origin are rare. An isolated single coronary artery is a congenital anomaly occurring in approximately 0.024-0.066% of the population. Atherosclerosis of these arteries is not infrequent with potentially severe consequences, but interventional procedures are rarely performed. We report an acute coronary syndrome case due to a subtotal paraostial left anterior descending (LAD) occlusion of a single L-I type coronary artery. Another severe stenosis was also present at mid-LAD. The patient was successfully treated with transradial percutaneous coronary intervention (PCI). Our case shows that when the anatomy is suitable, complex PCI can be performed successfully in single coronary arteries.

Effect of high doses of magnesium on converting ibutilide to a safe and more effective agent

Ibutilide is a class III antiarrhythmic agent indicated for cardioversion of atrial fibrillation and atrial flutter to sinus rhythm (SR). The most serious complication of ibutilide is torsades de pointes (TdP). Magnesium has been successfully used for the treatment of TdP, but its use as a prophylactic agent for this arrhythmia has not yet been established. The present study investigated whether high dose of magnesium would increase the safety and efficacy of ibutilide administration. A total of 476 patients with atrial fibrillation or atrial flutter who were candidates for conversion to SR were divided into 2 groups. Group A consisted of 229 patients who received ibutilide to convert atrial fibrillation or atrial flutter to SR. Group B consisted of 247 patients who received an intravenous infusion of 5 g of magnesium sulfate for 1 hour followed by the administration of ibutilide. Then, another 5 g of magnesium were infused for 2 additional hours. Of the patients in groups A and B, 154 (67.3%) and 189 (76.5%), respectively, were converted to SR (p = 0.033). Ventricular arrhythmias (sustained, nonsustained ventricular tachycardia, and TdP) occurred significantly more often in group A than in group B (7.4% vs 1.2%, respectively, p = 0.002). TdP developed in 8 patients (3.5%) in group A and in none (0%) in group B (p = 0.009). The administration of magnesium (despite the high doses used) was well tolerated. In conclusion, the administration of high doses of magnesium probably makes ibutilide a much safer agent, and magnesium increased the conversion efficacy of ibutilide.

Hepatocellular carcinoma with invasion into the right atrium. Report of two cases and review of the literature

We report two rare cases of hepatocellular carcinoma with invasion into the right atrium. In both our cases, the patients had liver cirrhosis and were admitted to our department due to symptoms such as worsening of the jaundice, ascites and edema of the lower extremities. The diagnosis of the HCC was established when we found high levels of alpha-fetoprotein, and the patients underwent MRI and CT-scan that were indicative of HCC. The clinical suspicion of invasion of the RA by the tumor emerged from the presence of heart-related symptoms, such as dyspnea and chest discomfort. The patients underwent two-dimensional transthoracic echocardiogram, which revealed from the sub-costal view a mobile atrial mass protruding from the inferior vena cava. In conclusion, when a patient with a history of chronic hepatic disease presents with symptoms of right heart failure one must be cautious and should bear in mind that right heart involvement from a malignant tumor may be present.

Effect of antihypertensive treatment on lipids and fibrinogen: Greek multicentre study of cilazapril

The effect cilazapril (CLZ) treatment on serum lipids and fibrinogen was studied in 114 hypertensive patients for 18 weeks. Blood pressure, heart rate, lipid profile and fibrinogen were measured before and at the end of the study in all patients. Satisfactory blood pressure control was seen in 68% of the patients (group A) after 4 weeks of treatment with 5 mg CLZ monotherapy, while a single dose of chlorthalidone, 25 mg daily, was added to the therapeutic regimen of the remaining 32% of patients (group B) to achieve blood pressure control. We conclude that CLZ has a slight beneficial effect on the lipid profile and a significantly beneficial effect on fibrinogen, but its combination with a diuretic reverses this beneficial effect.

Vascular endothelium, mechanical properties of the arterial wall and local angiotensin converting enzyme inhibition

METHODS

An experimental model of in situ isolated carotid arteries was used to study the contribution made by angiotensin II (Ang II) towards the mechanical properties of the arterial wall in 12-week-old Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. The effects of local incubation with saralasin (Sar1-Thr8-Ang II, 10(-6) mol/l) and with lisinopril (5 x 10(-6) mol/l) on carotid compliance were compared to the effects of removing the endothelium and the effects of totally abolishing vasomotor tone with potassium cyanide (0.1 mg/ml).

RESULTS

With an intact endothelium, local incubation with lisinopril increased carotid compliance by 23% in WKY rats (P less than 0.05) and by 14% in SHR (P less than 0.01). Under the same experimental conditions, saralasin increased carotid compliance by 24% in WKY rats and 23% in SHR relative to control values (P less than 0.05 and P less than 0.001, respectively). Removal of the endothelium induced significant increases in carotid compliance in WKY rats (17%, P less than 0.01) and in SHR (33%, P less than 0.001). After removal of the endothelium, there was no further increase in carotid compliance with lisinopril in either strain. In contrast, saralasin induced further significant compliance increases in both strains (+18%, P less than 0.001, and +11%, P less than 0.01, in WKY and SHR, respectively). After the artery had been poisoned with potassium cyanide, there was no further increase in compliance relative to values obtained with saralasin in either strain with or without the endothelium.

CONCLUSIONS

These findings suggest that Ang II receptors have a major effect on the control of basal vasomotor tone of large arteries in both normotensive and hypertensive rats. Furthermore, the increase in carotid compliance induced by local incubation with saralasin and with angiotensin converting enzyme (ACE) inhibitors may involve similar mechanisms acting on smooth muscle angiotensin receptors.

Relationships between single-vessel coronary artery obstructions and wall motion dysfunction analyzed by four computer-based methods

We analyzed regional wall motion in 238 patients by using cineangiograms recorded in the 30 degrees right anterior oblique projection. The sample was divided into three groups: a normal group (n = 71), a group with isolated obstruction of the left anterior descending coronary artery and previous anterior myocardial infarction (n = 85), and a group with isolated obstruction of the right coronary artery and previous inferior myocardial infarction (n = 82). Both anterior and inferior groups also had motion abnormality within the corresponding anterior or inferior wall as judged by the qualitative analysis of cineangiograms. Four quantitative methods were compared: a long axis method and a center of mass method using internal reference systems, a method derived from the Stanford model and an area-based method using external reference systems. Normal regional values were determined from the normal group to evaluate the specificity and sensitivity of the methods. The area-based method was the most sensitive in the anterior infarction group, whereas the center of mass method was the most sensitive in the inferior infarction group. We conclude that there is no evidence that any method, among those tested, is superior to others for every expected location of wall motion abnormality.

[Pathogenesis of tachycardia in hyperthyroidism. Value of Holter monitoring and the use of a beta-blocker]

The mechanisms of tachycardia in hyperthyroidism were investigated by means of Holter recordings of heart rate in 45 patients, 33 of whom had sinus rhythm and were left untreated. In the remaining 12 patients, recordings were taken after 3 days of treatment with either propranolol (120 mg/day; 6 patients) or pindolol (15 mg/day; 6 patients). Propranolol is a beta-blocker devoid of intrinsic sympathetic activity whereas pindolol possesses such activity. Changes in heart rate under the influence of each of these drugs were compared with those observed in 96 controls similarly treated. The difference in baseline heart rare between day and night was significantly higher (p less than 0.01) in patients with hyperthyroidism (17 +/- 1 QRS/min) than in controls (13 +/- 1 QRS/min). Day and night heart rates were increased by pindolol, the increase in night heart rate being significantly greater (p less than 0.05) in patients with hyperthyroidism (23.4 +/- 4.9%) than in controls (11.6 +/- 2.6%). These results suggest that sinus tachycardia in hyperthyroidism is related to an increase in the number of myocardial beta-adrenoceptors. They also indicate that thyrotoxicosis should not be treated with beta-blockers possessing intrinsic sympathetic activity.

Ventricular function and arterial compliance in patients with congestive cardiomyopathy

In order to study the interrelationship between left ventricular afterload, estimated from the mean left ventricular wall stress, and the mechanical properties of the aorta, we have simultaneously measured systemic arterial compliance and left ventricular wall stress in 19 patients with congestive cardiomyopathy. The strong linear relationship between the ejection fraction of the left ventricle and systemic arterial compliance, and between left ventricular wall stress and systemic arterial compliance, suggests that systemic arterial compliance is an important determinant of left ventricular afterload and thus of left ventricular function.

[Value of long-term electrocardiography in patients with cerebral ischemic accidents]

Continuous 24 hour electrocardiography (Holter monitoring) was performed in 226 patients aged 20 to 85 years (mean 61 years) presenting with focal signs of a cerebrovascular accident (CVA). The technique was the same in all patients; the study was limited to paroxysmal atrial arrhythmias. Eighty four of the 226 patients examined had atrial arrhythmias which were already known in 39 patients before Holter monitoring. In the other 187 cases, the following results were obtained: 1) 9 patients (4,8%) had paroxysmal atrial fibrillation (AF), 2) 6 patients (3,2%) had paroxysmal atrial tachycardia (PAT), 3) 11 patients (5,9%) had runs of atrial extrasystoles, 4) 19 patients (10%) had isolated atrial extrasystoles (IAE). When patients with underlying cardiac disease constituting a diagnostic indicator for arrhythmia were excluded, the following incidences were obtained: AF = 3,7%, PAT = 2,7% and runs of atrial extrasystoles = 4,3%. The majority of these arrhythmias occurred in elderly patients in whom atrial arrhythmias are known to occur and may be asymptomatic. There were practical consequences of these results, i.e. antiarrhythmic and anticoagulant therapy in 12 patients (6,4%) alone. As Holter monitoring is also associated with a number of false negative results with respect to paroxysmal atrial tachycardia, we do not believe that this investigation should be offered routinely to patients with CVA in the absence of other clinical or electrocardiographic indications.

Systemic arterial compliance in patients with non obstructive cardiomyopathy (NOCM), and coronary artery disease (CAD)

Arterial compliance had been estimated in three groups of patients: control, NOCM, and CAD, from analysis of the arterial pressure curve. In the three groups, a simple first order Winkessel model had been validated during normal and post extrasystolic beats. The measured arterial compliance depends mainly on i the diastolic pressure, ii, the mechanical properties of the aorta and major arteries. For the same range of age and diastolic pressure, the arterial compliance was not significantly different in the three groups of patients. Because of the significant variations of the arterial compliance during slight modifications of the diastolic pressure, the lack of difference in the compliance of control, NOCM, and CAD patients may be attributed to similar arterial mechanical properties.

[Evaluation of left ventricular function in diabetics by studying systolic time intervals]

Systolic time intervals were measured before and four minutes after maximal exercise stress testing in 54 patients without obvious cardiac disease. Twenty seven patients (average age 46 years) had diabetes of over 5 years standing (group II); group I comprised 27 normal controls (average age 46 years). All patients underwent maximal treadmill stress testing using the Bruce protocol and the maximal heart rate was achieved without any signs of coronary insufficiency. No significant difference was observed in the basal systolic time intervals of the two groups. The difference was not significant 4 minutes after the stress test. However, when the changes before and after exercise were compared, the patients in group I had a significant increase in heart rate (p less than 0,001), a reduction in the duration of electromechanical systole (QB2; p less than 0,02) in the preejectional period (PEP; p less than 0,001) and in the PEP/LVET ratio: p less than 0,01, whilst left ventricular ejection time (LVET) remained unchanged. The patients in group II only showed an increase in heart rate (p less than 0,01) and LVET (p less than 0,001). The differences in the systolic time intervals after exercise between these two groups probably reflect a degree of cardiac dysfunction which is not apparent at rest.

[Effect of nitroglycerin and N-ethoxycarbonyl-3-morpholinosydnonomine on the walls of large arteries]

Systemic arterial compliance was measured in 20 patients with left ventricular failure due to congestive cardiomyopathy. The method consisted in evaluating arterial compliance by analysing the exponential fall of the arterial pressure curve on a simple visco-elastic model. In the patient group, significant correlations were found between arterial compliance and age (r = 0,64 ; p less than 0,01) and arterial compliance and systolic blood pressure (r = -0,58 ; p less than 0,001). These relationships suggest that arterial compliance depends on the height of the systolic blood pressure and/or the elasticity of the arterial walls. Two groups of patients were defined : Group I (10 patients) given a single oral dose of 7,5 mg of nitroglycerine (Lenitral), and Group II (10 patients) giben a single oral dose of 4 mg N ethoxycarbonyl-3-morpholinosydnonomine (Molsidomine). There was no significant difference in the hemodynamic parameters or arterial compliance between the two groups before administration of these drugs. However, systolic blood pressure was significantly lower (p less than 0,01) and compliance significantly higher (p less than 0,05) after treatment in Group II. In Group I, nitroglycerine caused a significant increase in compliance (p less than 0,01), a significant decrease in systolic (p less than 0,02) and mean blood pressure (p less than 0,05) whilst heart rate, cardiac output and total systemic resistance remained unchanged. In Group II, Molsidomine caused a significant increase in arterial compliance (p less than 0,01), a decrease in systolic (p less than 0,001), diastolic (p less than 0,01) and mean blood pressure (p less than 0,01) and in cardiac output (p less than 0,01), whilst heart rate and total systemic resistance remained unchanged. This study shows that both drugs studied had significant effects on the walls of the large arteries.

Detection of residual myocardial function in acute transmural infarction using postextrasystolic potentiation. A computerized angiographic study

Twelve subjects without clinical or hemodynamic heart failure, admitted for a first untreated anterior transmural myocardial infarction, were evaluated within the first 24 hours after the onset of symptoms. Pulmonary angiography was performed while a right ventricular extrastimulus was delivered every fourth beat at 50% of the RR interval to systematically analyze the basal and the postextrasystolic left ventricular frames. Left ventriculograms were quantitatively processed to determine the ejection fraction (EF) and the percentage of the end-diastolic circumference showing hypokinetic (%HK) or akinetic (%AK) areas. Left ventricular angiography was performed 1 month later in all cases at the same paced atrial heart rate to compare this final angiogram to the basal and the electrically induced postextrasystolic initial beats. During the 1-month period of the study none of these subjects had complications such as recurrent chest pain, heart failure or rhythm disturbances, and no drug administration was necessary. Comparing the basal cycle of the initial angiogram and the final cycle, a poor correlation was found between the corresponding values of EF (r = 0.34), %HK (r = 0.38) and %AK (r = 0.48). The correlations were much better when a comparison was made between the postextrasystolic cycle of the initial angiogram and the final cycle (EF, r = 0.84; %HK, r = 0.96; %AK, r = 0.95). These results indicate that, from the first day after a TMI, the analysis of the postextrasystolic frame allows accurate estimation of the final left ventricular function and regional wall motion abnormalities. Postextrasystolic potentiation may be useful in the acute state of transmural infarction to discriminate potentially reversible ischemic from definitely jeopardized areas.