Left Ventricular Mechano-Energetic Efficiency Identifies an Early Impairment of Myocardial Blood Flow in Arterial Hypertension

BACKGROUND

Arterial hypertension causes cardiac functional and structural alterations. In hypertensive patients without flow-limiting epicardial coronary artery disease, we investigated possible relationships between positron emission tomography/computed tomography-derived myocardial blood flow (MBF) and echocardiographic parameters of left ventricular (LV) performance, including mechano-energetic efficiency indexed for myocardial mass (MEEi).

METHODS

Seventy-eight patients with hypertensive without flow-limiting epicardial coronary artery disease underwent echocardiography, including MEEi computation, and cardiac positron emission tomography/computed tomography with assessment of MBF/mass ratio at rest and after stress and myocardial flow reserve. The lowest MEEi tertile (MEEi<0.031 mL/s/g) was compared to the merged second and third tertiles (MEEi≥0.031).

RESULTS

Patients in the lowest MEEi tertile were older, had higher systolic blood pressure and body mass index. They also had higher prevalence of LV hypertrophy, whereas lower resting and stress MBF/mass ratio. MEEi was significantly correlated with both resting (r=0.51; P<0.0001) and hyperemic (r=0.54; P<0.0001) MBF/mass ratios, whereas it was not related to myocardial flow reserve. Delta of MBF/mass ratio was lower in the lowest MEEi tertile than in the highest (P<0.0001). In separate multiple linear regression models, after adjusting for sex, systolic blood pressure, prevalence of LV hypertrophy, left atrial volume index, and diuretic therapy, the association between LV MEEi and both hyperemic (beta coefficient=0.44; P=0.003) and resting (beta coefficient=0.35; P=0.008) MBF/mass ratio remained significant.

CONCLUSIONS

In patients with hypertensive without flow-limiting epicardial coronary artery disease, low values of MEEi could detect an early LV dysfunction involving an impairment of both resting and hyperemic MBF/mass ratios. MEEi has the advantage of simpler detection, cheaper costs than positron emission tomography/computed tomography, and a lack of radiation exposure.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02211365.

150 ECHO-DERIVED LEFT VENTRICULAR MECHANO-ENERGETIC EFFICACY CHARACTERIZES HYPERTENSIVE PATIENTS WITH IMPAIRED PET-DERIVED MYOCARDIAL BLOOD FLOW

Background

Chronic left ventricular (LV) pressure overload determines both morphological and functional alterations in the heart and in the vascular system with occurrence of LV hypertrophy, coronary rarefaction and metabolic impairment, predisposing to heart failure. We aim at investigating early cardiac involvement in hypertensive disease by both Positron emission tomography (PET) and echo assessment and possible associations between alterations of PET-derived myocardial blood flow (MBF) and echocardiographic parameters of LV performance including mechano-energetic efficiency indexed for myocardial mass (MEEi), in a population of symptomatic hypertensive patients without flow-limiting epicardial coronary artery disease (CAD).

Methods

The study population included 78 symptomatic hypertensive patients without flow-limiting epicardial CAD. All patients underwent standard echocardiographic assessment, including evaluation of LV MEEi, and PET assessment with evaluation of MBF and MBF/mass ratio at rest and after stress and myocardial flow reserve (MFR).

Results

The study population included 67% males, 55% with dyslipidaemia, 42% with smoking habits and 21% obese. Prevalence of LV hypertrophy was of 43%. Among parameters of LV systolic performance, hyperaemic MBF/mass ratio resulted significantly correlated with LV MEEi (r=0.54, p&lt;0.0001), midwall fractional shortening (r=0.38, p=0.001) but not with LVEF (r=0.10, p=0.47). Similarly, resting MBF/mass ratio resulted to have statistically significant correlations with LV MEEi (r=0.51, p&lt;0.0001), midwall fractional shortening (r=0.29, p=0.01) but not with LVEF (r=0.11, p=0.39). LV MEEi reached the highest correlation coefficient with both resting and stress MBF/mass ratio. On the other hand, the correlation between MEEi and MFR did not reach statistical significance (r=0.11, p=0.33).

In a multiple linear regression analysis, after adjusting for sex, systolic blood pressure, prevalence of LV hypertrophy and therapy with diuretics, the association between LV MEEi and hyperaemic MBF/mass ratio remained significant (beta coefficient =0.40, p=0.007). In a subsequent multivariate model, adjusting for the same confounders, by replacing hyperaemic MBF/mass ratio with resting MBF/mass ratio, LV MEEi and resting MBF/mass ratio continued to be significantly associated (beta coefficient =0.32, p=0.015).

Conclusions

In a population of hypertensive patients without flow-limiting epicardial CAD, an early myocardial impairment possibly related to coronary rarefaction and inadequate angiogenesis contributing to the altered myocardial metabolic demand and efficacy is detectable by both PET and echo-derived LV MEEi. Indeed, an independent association between LV MEEi and both MBF/mass ratio at rest and after stress exists, LV MEEi having the advantage over PET of being easily derived from standard echocardiography and not needing radiation exposure.

Advanced imaging tools for evaluating cardiac morphological and functional impairment in hypertensive disease

Arterial hypertension represents a systemic burden, and it is responsible of various morphological, functional and tissue modifications affecting the heart and the cardiovascular system. Advanced imaging techniques, such as speckle tracking and three-dimensional echocardiography, cardiac magnetic resonance, computed tomography and PET-computed tomography, are able to identify cardiovascular injury at different stages of arterial hypertension, from subclinical alterations and overt organ damage to possible complications related to pressure overload, thus giving a precious contribution for guiding timely and appropriate management and therapy, in order to improve diagnostic accuracy and prevent disease progression. The present review focuses on the peculiarity of different advanced imaging tools to provide information about different and multiple morphological and functional aspects involved in hypertensive cardiovascular injury. This evaluation emphasizes the usefulness of the emerging multiimaging approach for a comprehensive overview of arterial hypertension induced cardiovascular damage.

Lifestyle-related risk factors, smoking status and cardiovascular disease

BACKGROUND

Cardiovascular disease represents one of the most important causes of morbidity and mortality in highly developed countries and is known to be associated with some lifestyle-related risk factors (e.g. alcohol consumption, smoking status, diet, physical activity, bodyweight). There is still incomplete information about their combined effect on cardiovascular risk in hypertensive patients with optimal pharmacological blood pressure control.

AIM

The objective of this study was to evaluate the correlation of some lifestyle behaviours, using a specific questionnaire, with development of cardiovascular disease in treated hypertensive patients.

METHODS

617 hypertensive, non-diabetic participants (aged 53.1 ± 7.6 years, 44.9% male; mean age 53.1 ± 7.6 years) free of prevalent cardiovascular disease, cancer, liver cirrhosis and/or failure, chronic kidney disease more than grade 3 (glomerular filtration rate by the Modification of Diet in Renal Disease study <30 mL/min/1.73 m2) were analysed. Metabolic syndrome was defined according to the Third Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Left ventricular hypertrophy was defined when left ventricular mass index was >51 g/m2. Carotid artery atherosclerosis was assessed as an increased intima medial thickness (IMT) by B-mode ultrasonography. IMT values between 0.9 and 1.3 mm were defined as 'thickening' and those >1.3 mm as 'plaque'. Assessment of smoking status, dietary and non-dietary factors was established by administration of a specific questionnaire.

RESULTS

In the initial population of examined patients, 288 were smokers and 329 were non-smokers. At baseline, the patients belonging to smoking group were less often overweight than those belonging to the non-smoking group, showing a lower initial body mass index (BMI) [27.54 ± 4.0 vs 28.28 ± 4.3; p < 0.029], lower plasma levels of high-density lipoprotein cholesterol (HDL-C) [48.14 ± 12.6 vs 51.39 ± 14.1 mg/dL; p < 0.006] and were more often affected by carotid artery atherosclerosis (93.9 % vs 86.1%; p < 0.002) than non-smoking patients. When analysed for dietary and other lifestyle-related risk factors, we found a higher prevalence of carotid atherosclerotic disease in patients consuming less than two meals per day than in those consuming more than two meals per day (96.6% vs 85.7%; p < 0.001), without any significant difference in the mean number of medications taken and in specific classes of medications. Total amount of cigarettes smoked, calculated as packs per year (39.14 ± 16.5 vs 20.81 ± 13.6; p < 0.0001) was higher in patients with a diagnosis of atherosclerotic disease of the carotid artery than in patients free of this disorder, whereas the average age at which people began smoking was lower (17.58 ± 6.3 vs 21.53 ± 10.2 years). In a binary model of logistic regression adjusted for BMI, HDL-C, smoking status and number of daily meals, only smoking status was confirmed to be strongly correlated to clinical evidence of carotid atherosclerosis (p < 0.025).

CONCLUSIONS

In hypertensive patients, in optimal blood pressure control, smoking status has been shown to be independently associated with an increased maximum arterial IMT (IMTmax). In particular, an increase of the IMT was associated with the total amount of cigarettes smoked (calculated as packs per year) and the average age at which people began smoking.

Prediction of long-term survival in chronic heart failure by multiple biomarker assessment: a 15-year prospective follow-up study

BACKGROUND

In chronic heart failure (CHF), several plasma biomarkers identify subjects at risk of death over the midterm. However, their long-term predictive value in the context of other candidate predictors has never been assessed. This information may prove valuable in the management of a chronic disease with a long natural history, as CHF is today.

HYPOTHESIS

We aimed to assess the very-long-term prognostic power of a set of biomarkers to identify CHF patients at highest risk for all-cause mortality.

METHODS

A group of 106 consecutive outpatients with CHF (85 male and 21 female, median age 56 y) was followed for 15 years. Echocardiographic tracings and blood samples were collected at study entry to evaluate cardiac function, plasma atrial natriuretic peptide (ANP), aldosterone, and erythropoietin, and plasma renin activity. The relationships between biomarkers, clinical and echocardiographic variables, and mortality were assessed.

RESULTS

After 15 years, 86 of the 106 patients (81%) had died. Multivariate analysis showed that ANP was the best independent predictor of survival over several clinical, echocardiographic, and humoral variables (hazard ratio: 5.62, 95% confidence interval: 3.37-9.39, P < 0.001 for plasma levels < median value of 71 pg/mL). Plasma renin activity and erythropoietin provided prognostic information in univariate analysis, but lost their predictive power when adjusted for covariates.

CONCLUSIONS

The present study represents the longest available follow-up of patients with CHF evaluating the prognostic power of multiple biomarkers. It shows that a simple assessment of plasma ANP levels is the strongest long-term predictor of death in all stages of heart failure.

Cardiac performance during exercise in patients with Fabry's disease

BACKGROUND

Fatigability and dyspnoea on effort are present in many patients with Fabry's disease. We assessed the determinants of cardiac performance during exercise in patients with Fabry's disease and preserved left ventricular ejection fraction at rest.

MATERIALS AND METHODS

Sixteen patients with Fabry's disease and 16 control subjects underwent radionuclide angiography at rest and during exercise, tissue Doppler echocardiography and magnetic resonance imaging at rest.

RESULTS

The exercise-induced change in stroke volume was +25 +/- 14% in controls and +5.8 +/- 19% in patients with Fabry's disease (P < 0.001). In 10 patients (group 1), the stroke volume increased (+19 +/- 10%), and in 6 patients (group 2) it decreased (-16 +/- 9%) with exercise. Patients of group 2 were older, had worse renal function, higher left ventricular mass and impaired diastolic function compared to group 1. The abnormal stroke volume response to exercise in group 2 was associated with a decrease in end-diastolic volume (P < 0.001) and a lack of reduction of end-systolic volume (P < 0.01) compared with both controls and group 1. The ratio of peak early-diastolic velocity from mitral filling to peak early-diastolic mitral annulus velocity was the only independent predictor of exercise-induced change in stroke volume (B -0.44; SE 0.119; beta-0.70; P < 0.005).

CONCLUSIONS

The majority of patients with Fabry's disease were able to augment stroke volume during exercise by increasing end-diastolic volume, whereas patients with more advanced cardiac involvement may experience the inability to increase cardiac output by the Frank Starling mechanism.

[Usefulness of a telematic system and image analysis in the follow-up of high-risk patients: a new health service model]

BACKGROUND

Inadequate blood pressure control in hypertensive patients is in contrast with the evidence from clinical studies of effectiveness of the same antihypertensive compounds used in clinical practice. These results may be due to follow-up management of hypertensive patients and in particular to the interaction between general practitioners (GPs) and hypertension specialists. The aim of this study was to assess the effectiveness of an internet-based digital network, connecting specialists and GPs in the Campania Region, on blood pressure control and major cardiovascular events.

METHODS

A network between the Hypertension Center of "Federico II" University, 14 specialist centers and 60 GPs was done in the Campania Region (Campania Salute Project, CS). Randomized GPs enrolled in CS could update online clinic records of patients (n = 1979). As a control group, we included 2045 patients referred to the specialist centers by GPs from outside the network. All patients completed a 2-year follow-up.

RESULTS

CS determined a significant reduction in systolic and diastolic blood pressure (CS group 144 +/- 18/91 +/- 11 vs 136 +/- 17/86 +/- 10 mmHg; control group 144 +/- 17/90 +/- 10 vs 139 +/- 15/87 +/- 9 mmHg, p < 0.001). Indeed, the CS group showed less frequent fatal and non-fatal major cardiovascular events (2.9 vs 4.3%, chi2 = 5.047, p < 0.02).

CONCLUSIONS

Our results support the hypothesis that telematic connections may contribute to improve blood pressure control and reduce major cardiovascular events.

The use of a telematic connection for the follow-up of hypertensive patients improves the cardiovascular prognosis

BACKGROUND

Inadequate blood pressure (BP) control could be due to incorrect management of hypertensives caused by the lack of interaction between general practitioners (GP) and hypertension specialists.

OBJECTIVES

To test the effectiveness on BP and total cardiovascular risk (TCVR) control of an internet-based digital network connecting specialists and GPs.

METHODS

We created a network among the Hypertension Clinic, Federico II University (Naples, Italy), 23 hospital-based hypertension clinics and 60 GPs from the area (CampaniaSalute Network, CS). Randomized GPs enrolled in CS could update online records of patients (n = 1979). As a control, we included 2045 patients referred to the specialist clinics by GPs from outside the network. All patients completed a 2-year follow-up.

RESULTS

CS provided a larger reduction in BP [systolic/diastolic BP (SBP/DBP): 7.3 +/- 0.4/5.4 +/- 0.3 versus 4.1 +/- 0.4/3.1 +/- 0.26 mmHg, CS versus control; P < 0.001 for both] and percentage of patients with BP < 140/90 mmHg (CS versus control: baseline, 33 versus 34%, NS; end of follow-up, 51 versus 47%, chi = 13.371; P < 0.001). A European Society of Hypertension-European Society of Cardiology (ESH/ESC) TCVR score was calculated [from 1 (average) to 5 (very high TCVR)]. The CS group showed a reduction in the mean TCVR score (CS: from 3.5 +/- 0.02 to 3.2 +/- 0, P < 0.01, ANOVA; control group: 3.5 +/- 0.03 to 3.4 +/- 0.03, NS) and, accordingly, fatal and non-fatal major cardiovascular events (MACE) were less frequent (2.9 versus 4.3%; chi = 5.047, P < 0.02). CS predicts fewer MACE in multiple binary regression analysis (beta:-7.27, P < 0.008) reducing the risk for MACE compared to control [odds ratio (OR): 0.838; 95% confidence interval (CI): 0.73-0.96].

CONCLUSION

Our results support the idea that telemedicine can achieve better control of BP and TCVR.