Antoine Cremer

ECG detection of left ventricular hypertrophy: the simpler, the better?

Objective: ECG is commonly employed to identify left ventricular hypertrophy (LVH) and a high risk of cardiovascular events (CVE) in hypertensive patients. However, the multiplicity of the existing criteria does not simplify interpretation of the data. We compared a number of common criteria in hypertensive patients by taking as references left ventricular mass (LVM) measured by echocardiography and prediction of incident CVE. Methods: The population was a cohort of 958 hypertensive patients (mean age 48 years) recruited before any treatment and having benefited from an ECG and an echocardiography. We evaluated their outcomes at regular intervals. We examined the relationships between several ECG criteria of LVH and LVM as well the occurrence of CVE. Results: Among the various parameters tested (Sokoloff, Cornell, Cornell product) the simple measurement of the RaVL wave offered the best correlations to LVM and the best prediction of the existence of an echocardiographic LVH (receiver-operating characteristic curves). Its alterations were best correlated with the changes in LVM during the follow-up period. Moreover, this simple measurement offered the best performance for the prediction of the occurrence of CVE (123 events after a mean lapse of 12 years). Conclusion: In the interpretation of an ECG in the hypertensive patient, the single measurement of the R wave in aVL gives results at least as good as those of more complicated indices, which do not appear to contribute further to the diagnosis of LVH and the prediction of cardiovascular risk.

Prognostic value of the extent of left ventricular hypertrophy and its evolution in the hypertensive patient.

Objective: Left ventricular hypertrophy (LVH) is a marker of cardiovascular risk. However, the progression of the risk as a function of the course of the LVH has only been the subject of few studies. Methods: We report the consequences of the evolution of the left ventricular mass (LVM) in a cohort of hypertensive patients whose LVM was measured before any antihypertensive treatment. Results: We followed up for an average of 12 years, 763 hypertensives with LVM measurement by echocardiography on inclusion. In this population, 117 cardiovascular complications occurred and the initial LVM appeared to be the most powerful marker of risk. A cutoff of 51 g/m2.7 for the LVM index (LVMI) offered the best compromise of sensitivity and specificity in the prediction of complications. A second determination of LVM was carried out in 436 patients on average 5 years after inclusion. In this sub-group, 82 complications were recorded after an average interval of 13 years. The 51 g/m2.7 value of LVMI over the follow-up offered the same sensitivity (74%) and specificity (52%) in the prediction of complications. The progression of the LVM was related to the occurrence of complications independently of the basal value and other risk factors. Conclusions: We confirm LVMI as a powerful risk factor in hypertension with a cutoff of 51 g/m2.7, which offers the same sensitivity and specificity whether the LVM was determined before or during treatment. The progression of LVM, on average 5 years after the initial measurement had a prognostic value independent of the initial determination.

Determination of central blood pressure by a noninvasive method (brachial BP and QKD interval)

Background: The measurement of central blood pressure (BPc) has become a matter of importance. Several therapeutic trials have noted a different protective effect against cardiovascular complications with different antihypertensive strategies, but an identical decrease in brachial BP (BPb). A possible explanation lies in the different effects of the treatments on BPc. We propose a new noninvasive method for the automatic measurement of BPc based on the QKD interval, an arterial stiffness marker. Materials and methods: This study was carried out on patients referred for cardiac catheterization. We simultaneously measured the central SBP (SBPc) invasively with a pigtail probe, and the BPb by a cuff coupled with recording of the QKD interval. Two cohorts were studied, one to define an algorithm of SBPc estimation and one to validate this algorithm. Results: The first cohort included 65 patients. We performed 136 simultaneous measurements. In the multivariate analysis, four variables were significantly correlated with SBPc: mean BPb (mBPb), QKD, height and heart rate (HR) with the following regression equation: SBP = 105 + 1.29 × mBPb − 0.39 × HR − 0.30 × height − 0.11 × QKD This equation estimated 81% of the variance of the invasive SBPc ± 13 mmHg. This algorithm was then tested in another cohort of 80 patients. Difference between measured and estimated SBPc was 2 ± 14 mmHg. Conclusion: This study showed that it is possible to estimate SBPc by simultaneous measurement of QKD and BPb. If further studies confirm these results, a noninvasive ambulatory method of monitoring of SBPc could be employed in clinical practice.

Arterial Stiffness From Monitoring of Timing of Korotkoff Sounds Predicts the Occurrence of Cardiovascular Events Independently of Left Ventricular Mass in Hypertensive Patients

Several studies have established that the increase in arterial stiffness (AS) is a cardiovascular risk factor but to date no studies have evaluated in hypertensive patients its prognostic value in comparison with another powerful risk factor, left ventricular mass (LVM) as measured by echocardiography. We prospectively evaluated the prognostic value of AS and LVM in patients with essential hypertension. The population studied comprised 793 patients (56% men) aged 54±14 years. For 519 patients, baseline measurements were made before any antihypertensive treatment, for 274 patients, the measurement were obtained during the follow-up period under antihypertensive treatment. AS was assessed from ambulatory monitoring of blood pressure and timing of Korottkoff sounds. Left ventricular mass was measured in 523 patients. After a mean follow-up of 97 months, 122 cardiovascular events were recorded in the whole population and 74 in the group with LVM determination. AS as continuous or discontinuous variable was independently related to cardiovascular events. The existence or not of antihypertensive treatment at the time of its measurement did not affect its prognostic value. When LVM was forced in the model, AS remained significantly related to cardiovascular events. Thus, AS has an independent prognostic value in the hypertensive, whether measured before or after the administration of antihypertensive treatment. This prognostic value persists after taking LVM into account.

Twenty-Four-Hour Blood Pressure Monitoring to Predict and Assess Impact of Renal Denervation: The DENERHTN Study (Renal Denervation for Hypertension).

The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure (BP) lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report here the effect of denervation on 24-hour BP and its variability and look for parameters that predicted the BP response. Patients with resistant hypertension were randomly assigned to denervation plus stepped-care treatment or treatment alone (control). Average and standard deviation of 24-hour, daytime, and nighttime BP and the smoothness index were calculated on recordings performed at randomization and 6 months. Responders were defined as a 6-month 24-hour systolic BP reduction ≥20 mm Hg. Analyses were performed on the per-protocol population. The significantly greater BP reduction in the denervation group was associated with a higher smoothness index (P=0.02). Variability of 24-hour, daytime, and nighttime BP did not change significantly from baseline to 6 months in both groups. The number of responders was greater in the denervation (20/44, 44.5%) than in the control group (11/53, 20.8%; P=0.01). In the discriminant analysis, baseline average nighttime systolic BP and standard deviation were significant predictors of the systolic BP response in the denervation group only, allowing adequate responder classification of 70% of the patients. Our results show that denervation lowers ambulatory BP homogeneously over 24 hours in patients with resistant hypertension and suggest that nighttime systolic BP and variability are predictors of the BP response to denervation. Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Orthostatic Hypotension and Risk of Incident DementiaNovelty and Significance: Results From a 12-Year Follow-Up of the Three-City Study Cohort

Several studies indicate a potential link between orthostatic hypotension (OH) and incident dementia but without substantial evidence to date. Our objective is to study the association between OH and dementia in a cohort of elderly individuals. To do so, baseline lying and standing blood pressure measurements were taken from 7425 subjects in the Three-City study. These subjects were then followed-up for 12 years. Cox proportional hazard models, adjusted for potential confounders, were used to estimate the risk of incident dementia according to OH status. Sensitivity analysis was performed using the so-called illness-death model, a specific statistical method which takes into account competitive risk with death. OH frequency was found to be around 13%, and 760 cases of dementia were diagnosed during follow-up. We observed significant associations between the presence of OH at baseline and the occurrence of dementia during the follow-up, with an increased risk of at least 25% observed regardless of the OH threshold and the statistical method used. In conclusion, there is an association between OH and dementia. Considering that OH is a common condition and is easy to measure, OH measurements could help to identify subjects with higher risk of dementia. Moreover, reducing OH could be a step to prevent conversion to dementia.

Increased arterial stiffness is an independent predictor of atrial fibrillation in hypertensive patients.

Objective: Atrial fibrillation is the most common arrhythmia, and confers a high risk of stroke and heart failure. Hypertension and ageing are two important risk factors of incident atrial fibrillation and are both associated with increased arterial stiffness. The possible relationship between arterial stiffness and atrial fibrillation is insufficiently documented and is probably complex. We tested these relations in a cohort of hypertensive patients. Methods: The population belongs to a registry which includes patients referred before administration of antihypertensive treatment and fulfilling the following criteria: office blood pressure (BP) above 140/90 mmHg, essential hypertension, no history of cardiovascular events, type 1 diabetes or atrial fibrillation, 24-h ambulatory measurement of BP coupled with the measurement of timing of Korotkoff sounds to assess arterial stiffness [indexed theoretical value of QKD interval for a SBP of 100 mmHg, at heart rate (HR) of 60 b.p.m., indexed for height and QRS duration (QKDh)]. An echocardiographic examination was carried out at baseline in the majority of patients. Atrial fibrillation-free survival was analysed with a Cox model including sex, diabetes, smoking, hypercholesterolaemia, QKDh, average 24-h pulse pressure and mean BP, mean 24-h HR, BMI and left atrial diameter (LAD), when available. Results: We included 853 patients and recorded 67 new onsets of atrial fibrillation (mean follow-up = 102 ± 62 months). Analysis found three variables significantly and independently linked to the occurrence of atrial fibrillation: age, QKDh and 24-h average HR. When LAD was introduced (n = 480, 35 incident atrial fibrillation), three variables were linked to incident atrial fibrillation: age, QKDh and LAD. Conclusion: Arterial stiffness is a strong predictor of future atrial fibrillation in hypertensive patients, independently of age, 24-h pulse pressure and LAD.

Determination of central blood pressure by a noninvasive method (brachial blood pressure and QKD interval): a noninvasive validation.

Objective: We validated against invasive measurements a measure of central SBP based on the QKD interval. The present objective is a comparison to the SphygmoCor device. Materials and methods: A first cohort was used to redefine an algorithm for estimating ascending aorta SBP (cSBP) with respect to SphygmoCor. This algorithm was then tested in a second cohort under static conditions and in a third cohort during a head-up tilt to study blood pressure variations. Results: The first cohort (36 patients, mean age: 46 ± 20 years, SBP: 114 ± 19 mmHg) defined the estimation algorithm as cSBP = 62.687 + 1.35 × meanBP-0.207 × heart rate−0.251 × height−0.1 × QKD (mean difference with SphygmoCor = 0 ± 7 mmHg). In the second cohort (105 patients, mean age: 51 ± 19 years, SBP: 132 ± 22 mmHg), the average difference between the two techniques was 2 ± 6 mmHg (R2 = 0.93). The dynamic cohort included 31 patients (mean age: 49 ± 23 years, SBP: 110 ± 19 mmHg) with 224 pairs of measurement. We studied the changes in central blood pressures compared with the basal state of each of the two techniques during head-up tilt. With QKD, the average cSBP was 104 ± 19 mmHg, the average variation was −13.00 mmHg ± 15 (range 7–74 mmHg). With SphygmoCor, average cSBP was 101 mmHg ± 18, the average variation was −14 mmHg ± 16 (range 2–81 mmHg). The variations in blood pressure with the two techniques were well correlated (R2 = 0.93). Conclusion: cSBP estimation based on the QKD interval is comparable in precision to the SphygmoCor. Its ability to measure cSBP variations suggests that it could be employed for ambulatory measurements over 24 h.

Investigating the association of vitamin D with blood pressure and the renin–angiotensin–aldosterone system in hypertensive subjects: a cross-sectional prospective study

The hypothesis that vitamin D (25(OH)D) insufficiency plays a role in occurring of various disease has led to a rise in requests of dosages and to an increase of health-care costs. 25(OH)D insufficiency is associated with increased risk of cardiovascular disease and hypertension in many studies. Animal studies demonstrated that 25(OH)D insufficiency activates renin angiotensin system but corresponding humans data are limited. The aim of the study was to document relationship between 25(OH)D, blood pressure, and renin angiotensin system in hypertensive subjects. In all, 248 hypertensive individuals, 46.8 years (±14), were hospitalized for an etiological assessment of hypertension in this cross-sectional study over two calendar years. 25(OH)D, plasma renin activity, and aldosterone were determined in stringent conditions and blood pressure was measure. Statistical analyses were carried out to analyze the association between 25(OH)D, blood pressure, and renin angiotensin system using linear and logistic regressions with adjustments on relevant variables. In all, 80% of the studied population had a 25(OH)D insufficiency. There were no significant association between 25(OH)D and levels of systolic or diastolic blood pressure, plasma renin activity, and aldosterone whatever the statiscal method used after adjustment. 25(OH)D is not associated with blood pressure and renin angiontensin component in hypertensive subjects. These results corroborate the interventional studies which are for a large majority negatives. A new definition of the 25(OH)D insufficiency in general population is necessary.

ESC Council on hypertension position document on the management of hypertensive emergencies

Hypertensive emergencies are those situations where very high blood pressure (BP) values are associated with acute organ damage, and therefore, require immediate, but careful, BP reduction. The type of acute organ damage is the principal determinant of: (i) the drug of choice, (ii) the target BP, and (iii) the timeframe in which BP should be lowered. Key target organs are the heart, retina, brain, kidneys, and large arteries. Patients who lack acute hypertension-mediated end organ damage do not have a hypertensive emergency and can usually be treated with oral BP-lowering agents and usually discharged after a brief period of observation.