Association between Left Ventricular Diastolic Dysfunction and Renal Hemodynamic Change in Patients with Treated Essential Hypertension

Renal Dysfunction and Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) and chronic kidney disease (CKD) constitute a high-risk phenotype with significant morbidity and mortality and poor prognosis. Multiple proinflammatory comorbid conditions influence the pathogenesis of HFpEF and CKD. Renal dysfunction in HFpEF is a consequence of the complex interplay between hemodynamic factors, systemic congestion, inflammation, endothelial dysfunction, and neurohormonal mechanisms. In contrast to heart failure with reduced ejection fraction, there is a dearth of effective targeted therapies for HFpEF. Tailoring study design toward the different phenotypes and delving into their pathophysiology may be fruitful in development of effective phenotype-specific targeted pharmaceutical therapies.

Renal Resistive Index of the Main Renal Arteries and Transmitral Flow in Hypertensive Patients

In hypertensive patients, diastolic dysfunction is related to increased resistive index (RI) of parenchymal renal arteries. To determine the existence of a link between RI of the main renal arteries (RRI) and diastolic dysfunction, a group of 127 hypertensive patients, with glomerular filtration rates >50 mL/min (mean estimated glomerular filtration rate: 88.6 ± 15.2 mL/min) and no comorbidities, was studied. RRI and transmitral flow were evaluated using the deceleration time (DT) and E/A ratio. A statistically significant correlation between RRI and DT (>240 ms) was noted (p < 0.001). The RRI cutoff that best discriminated patients with DT >240 ms was 0.675. For each unitary increment of 10 mm in DT, the log-transformed RRI significantly increased by a mean of 0.006 point (p < 0.001). This study revealed the importance of the link between RRI and transmitral DT in addition to the renowned significance of the increase in RI as a cardiovascular risk factor in hypertensive patients without comorbidities.

The association between the renal resistive index and the myocardial performance index in the general population

OBJECTIVE

The renal resistive index (RRI) is the most described measure of renal hemodynamics. The myocardial performance index (MPI) is widely used to assess overall myocardial performance. In this study, we aimed to investigate the relationship between renal hemodynamics, assessed by the RRI, and cardiac functions, assessed by the MPI in the general population.

METHODS

This single-center, cross-sectional study included a total of 302 consecutive patients who presented to our outpatient cardiology clinic between October 2019 and February 2020. All patients underwent transthoracic echocardiography and renal Doppler ultrasonography. The study population was divided into two groups: low RRI group (RRI ≤ 0.7, n = 236) and high RRI group (RRI > 0.7, n = 66).

RESULTS

E/A ratio, left ventricular ejection fraction (LVEF), and the MPI were significantly higher in the high RRI group than in the low RRI group (61.3 ± 15.4 vs 55.3 ± 16.4, P = .010 for E velocity; 0.9 ± 0.3 vs 0.7 ± 0.2, P = .008 for E/A ratio; 57.7 ± 4.7 vs 53.2 ± 10.1, P = .029 for LVEF; 0.52 ± 0.1 vs 0.43 ± 0.1, P < .001 for the MPI). A stepwise linear regression analysis demonstrated that LVEF (β = .123, P = .026), E velocity (β = .221, P < .001), and the MPI (β = .392, P < .001) were independently associated with the RRI.

CONCLUSION

Left ventricular ejection fraction and intra-cardiac Doppler blood flow indices, including E velocity and the MPI, were significantly and independently associated with the RRI in the general population.

Associations between increased renal resistive index and cardiovascular events

BACKGROUND AND PURPOSE

Chronic kidney disease is a risk factor for cardiovascular disease (CVD). Renal resistive index (RI) measured by Doppler ultrasonography is associated with renal impairment. We investigated the relationship between RI and cardiac function, and evaluated the utility of RI for predicting cardiac events in patients with CVD.

METHODS AND RESULTS

Renal Doppler ultrasonography and echocardiography were performed in a total of 452 patients with CVD. Correlations of RI with serum creatinine and estimated glomerular filtration rate (eGFR) were significant but not strong (r = 0.37, p < 0.001; r = -0.42, p < 0.001, respectively). RI correlated positively with age, left atrial volume index, left ventricular mass index, and early transmitral velocity to mitral annular early diastolic velocity (e') ratio (E/e'), and showed significant negative correlations with e' and diastolic blood pressure. Between two subgroups-112 patients hospitalized with cardiovascular events (Group A) and 200 age- and eGFR-matched controls (Group B)-RI was significantly higher in Group A than in Group B, although age and eGFR were similar.

CONCLUSIONS

RI reflects the impairment of intrarenal hemodynamics that cannot be adequately elucidated by eGFR alone. Assessment of renal RI may be useful in conjunction with prognostic estimates for patients with CVD.

Doppler indexes of left ventricular systolic and diastolic flow and central pulse pressure in relation to renal resistive index

BACKGROUND

The cardio-renal interaction occurs via hemodynamic and humoral factors. Noninvasive assessment of renal hemodynamics is currently possible by assessment of renal resistive index (RRI) derived from intrarenal Doppler arterial waveforms as ((peak systolic velocity - end-diastolic velocity)/peak systolic velocity). Limited information is available regarding the relationship between RRI and cardiac hemodynamics. We investigated these associations in randomly recruited subjects from a general population.

METHODS

In 171 participants (48.5% women; mean age, 52.2 years), using pulsed wave Doppler, we measured RRI (mean, 0.60) and left ventricular outflow tract (LVOT) and transmitral (E and A) blood flow peak velocities and its velocity time integrals (VTI). Using carotid applanation tonometry, we measured central pulse pressure and arterial stiffness indexes such as augmentation pressure and carotid-femoral pulse wave velocity.

RESULTS

In stepwise regression analysis, RRI independently and significantly increased with female sex, age, body weight, brachial pulse pressure, and use of β-blockers, whereas it decreased with body height and mean arterial pressure. In multivariable-adjusted models with central pulse pressure and arterial stiffness indexes as the explanatory variables, we observed a significant and positive correlation of RRI only with central pulse pressure (P < 0.0001). Among the Doppler indexes of left ventricular blood flow, RRI was significantly and positively associated with LVOT and E peak velocities (P ≤ 0.012) and VTIs (P ≤ 0.010).

CONCLUSIONS

We demonstrated that in unselected subjects RRI was significantly associated with central pulse pressure and left ventricular systolic and diastolic Doppler blood flow indexes. Our findings imply that in addition to the anthropometric characteristics, cardiac hemodynamic factors influence the intrarenal arterial Doppler waveform patterns.

The beneficial impact of fasudil and sildenafil on monocrotaline-induced pulmonary hypertension in rats: a hemodynamic and biochemical study

Pulmonary arterial hypertension (PAH) still cannot be cured effectively, hence the search for novel treatments continues. The effects of sildenafil (25 mg/kg body weight) and fasudil (30 mg/kg body weight) given alone or in combination, on normalization of right ventricular pressure (RVP), right ventricle mass, as well as the levels of several biomarkers (HDL-C, BNP, VEGF-A), were assessed in a rat model of monocrotaline (MCT)-induced PAH. MCT (60 mg/kg body weight) induced clear PAH in male Wistar rats. After 21 days, a significant decrease in RVP accompanied by a reduction of right ventricular hypertrophy - a significant decrease in the right ventricle/left ventricle plus septum ratio - as a result of sildenafil or fasudil administration was assessed. The administration of fasudil and sildenafil alone or in combination caused a significant decrease in plasma BNP level as compared to MCT-treated rats. Fasudil alone or with sildenafil, but not sildenafil alone, significantly increased HDL-C level as compared to MCT-treated rats. Fasudil and sildenafil given alone or in combination caused a significant increase in plasma VEGF-A level as compared to rats exposed to MCT.

Left ventricular hypertrophy and abdominal aorta size in essential hypertension

AIM

To investigate the association between subclinical organ damage and abdominal aortic diameter in a large cohort of uncomplicated essential hypertensive patients.

METHODS

Subclinical markers of organ damage (i.e. left ventricular mass, carotid intima-media thickness and plaques, microalbuminuria and retinal changes) and abdominal aortic diameter (ultrasonography) were assessed in 2430 (mean age 53 ± 13 years) untreated and treated hypertensive patients included in the Evaluation of Target Organ Damage in Hypertension (ETODH) study.

RESULTS

In the whole study population, left ventricular mass index was the most important correlate (β = 0.418, P < 0.0001) of the absolute abdominal aortic diameter and, after age, (β = 0.268, P < 0.0001) of abdominal aortic diameter indexed to body surface area (abdominal aorta index, AAI). In a sex-based analysis, a stepwise increase in left ventricular mass index as well as in prevalence of left ventricular hypertrophy (LVH), carotid intima-media thickness and plaques occurred from the lower to the upper quartile of AAI in men, but not in women. No correlations were found between AAI and microalbuminuria or retinal changes.

CONCLUSION

Our findings support a sex-specific relation between abdominal aorta size and subclinical organ damage by showing that LVH in hypertensive men is an independent correlate for enlarged abdominal aorta. On the basis of these data, diagnostic protocols for detecting subclinical alterations in the abdominal aorta should be optimized.

Renal vascular response to angiotensin II inhibition in intensive antihypertensive treatment of essential hypertension

INTRODUCTION

High blood pressure (BP) leads to target organ damage. It is suggested that regression of early organ lesions is possible on condition of BP normalization. The study objective was to assess whether permanent reduction of BP to the recommended values modifies renal vascular response to acute angiotensin II inhibition in the Doppler captopril test (DCT) in patients with essential hypertension (EH).

MATERIAL AND METHODS

Twenty-nine persons (58 kidneys) were found eligible for the study: 18 patients with EH and 11 healthy volunteers constituting the control group. Glomerular filtration rate estimation (eGFR), 24-h ambulatory BP monitoring (ABPM) and DCT with evaluation of renal resistive index change (ΔRI) were performed before and after a 6-month period of intensive antihypertensive therapy (IAT). Additional ABPM was performed at the end of IAT.

RESULTS

The mean IAT period was 8.5 ±2.4 months. The mean 24-h values of systolic and diastolic BP in the EH group were significantly lower in the IAT period than at the beginning and at the end of the study. Significantly lower systolic and diastolic BP (p < 0.05) and improvement of renal function (eGFR 121 ±38 vs. 139 ±40 ml/min, p < 0.001) were found after IAT as compared to initial values. Before IAT, ΔRI was significantly lower in the EH group as compared to the controls, but no such differences were found after IAT.

CONCLUSIONS

In EH patients, intensive BP lowering to the recommended values was associated with improvement of renal function and normalisation of renal vascular response to acute angiotensin II inhibition.

Long-Term Vardenafil Therapy Improves Hemodynamics in Patients with Pulmonary Hypertension

The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.