Association between Altered Circadian Blood Pressure Profile and Cardiac End-Organ Damage in Patients with Renovascular Hypertension

Atherosclerotic renal artery stenosis, mediating biomarkers, and risk of cardiac among individuals with hypertension: A real-world study

Background

Atherosclerotic renal artery stenosis (ARAS) is commonly associated with cardiovascular diseases(CVD). Patients with ARAS typically present with cardiac structural and functional abnormalities, and the differences in cardiac structure and function compared to hypertensive patients without ARAS remain to be explored.

Methods

A total of 499 hypertensive patients were included, of whom 134 had ARAS and 365 had no renal artery stenosis (RAS). Parameters about cardiac function and structure detected by echocardiography and other clinical data are collected. Univariate and multivariate binary logistic regression and mediation analysis were performed on the collected data.

Results

Compared to hypertensive patients without ARAS, those with ARAS had significantly increased left ventricular (LV) internal diameter (LVIDd), posterior wall thickness (PWTd), LV geometric abnormalities, diastolic dysfunction, and a higher prevalence of LV hypertrophy (LVH). After adjustment, ARAS was significantly associated with LV diastolic dysfunction (LVDF) (OR = 1.12, 95 %CI = 1.03-1.3), LVIDd (OR = 1.07, 95 %CI = 1.02-1.13), LV geometry (OR = 1.24, 95 %CI = 1.12-1.36), PWTd (OR = 1.2, 95 %CI = 1.09-1.31), and LV mass index (OR = 1.31, 95 %CI = 1.18-1.47). Mediation analysis identified hypersensitive C-reactive protein (Hs-CRP) and serum creatinine (Scr) as significant mediators, accounting for 10.80 % to 59.54 % of the ARAS impact on LV abnormalities.

Conclusion

ARAS appears to be an independent risk factor for abnormalities in cardiac function and structure, potentially mediated by Hs-CRP and Scr. Hypertensive patients with ARAS demonstrate a higher prevalence of left ventricular hypertrophy (LVH) and diastolic dysfunction, underscoring the importance of vigilant monitoring in this population.

Impact of extracardiac vascular disease on outcomes of 1.4 million patients undergoing percutaneous coronary intervention

OBJECTIVES

Extracardiac vascular disease (ECVD) is increasingly recognized as a cardiovascular risk factor, but its association with outcomes after percutaneous coronary intervention (PCI) has not been well characterized.

METHODS

Using the National Inpatient Sample database, all patients undergoing PCI between October 2015 and December 2018 were stratified by the presence and organ-specific extent of extracardiac vascular comorbidity (cerebrovascular disease (CeVD), renovascular, aortic and peripheral arterial disease (PAD)). Primary outcome was all-cause mortality and secondary outcomes were (a) major adverse cardiovascular and cerebrovascular events (MACCE), (b) acute ischemic stroke and (c) major bleeding. Multivariable logistic regression was used to determine the adjusted odds ratios (aOR) and 95% confidence interval (95% CI).

RESULTS

Of a total of 1,403,505 patients undergoing PCI during the study period, 199,470 (14.2%) had ECVD. Patients with ECVD were older (median of 72 years vs. 70 years, p < 0.001) and had higher comorbidity burden that their counterparts. All cause-mortality was 22% higher in patients with any ECVD compared to those without ECVD. PAD patients had the highest odds of all-cause mortality (aOR 1.48, 95% CI 1.40-1.56), followed by those with CeVD (aOR 1.15, 95% CI 1.10-1.19). Patients with extracardiac disease had increased odds of MACCE, ischemic stroke and bleeding, irrespective of the nature or extent (p < 0.05), compared to patients without ECVD.

CONCLUSION

ECVD is associated with worse outcomes in patients undergoing PCI including significantly higher rates of death and stroke. These data should inform our shared decision-making process with our patients.

Renal artery stenosis and left ventricular hypertrophy: an updated review and meta-analysis of echocardiographic studies

AIM

Data on left ventricular hypertrophy (LVH) in patients with renal artery stenosis (RAS) and its regression following renal revascularization are scanty. We performed a meta-analysis to provide comprehensive information on this clinically relevant issue.

METHODS

Full articles providing data on: LVH, as assessed by echocardiography, in RAS patients as compared with essential hypertensive counterparts; changes of left ventricular (LV) mass index after renal artery revascularization were considered.

RESULTS

A total of 905 study participants (RAS = 446, essential hypertensive = 459) of both sex were included in nine studies. Pooled LV mass index was higher in RAS than in essential hypertensive patients (140.4 ± 11.1 g/m versus 121.8 ± 6.2 g/m, standard mean difference being 0.41 ± 0.07 [95% confidence interval (CI) 0.27-0.51, P < 0.001]. Among 360 RAS patients undergone renal revascularization from eight studies, baseline and post-intervention pooled mean LV mass index values were 129.0 ± 10.2 g/m and 115.5 ± 9.9 g/m, respectively, the standard mean difference being-0.36 ± 0.06 (95% CI from -0.47 to -0.25, P < 0.001). These findings were unaffected by publication bias or single study effect.

CONCLUSION

Our meta-analysis indicates that RAS patients have an increased likelihood of LVH compared with essential hypertensive counterparts and renal artery revascularization has a beneficial effect on LV structure, as reflected by a significant decrease in LV mass index.

Blockade of the renin-angiotensin system in hypertensive patients with atherosclerotic renal artery stenosis

Renin angiotensin system (RAS) blockers are generally considered as contraindicated when an atheromatous renal artery stenosis (ARAS) is diagnosed. The main reason is the fear of inducing renal ischemia and, hence, accelerating renal fibrosis and the progression towards end stage renal disease, albeit RAS blocker have been shown to be highly effective in controlling blood pressure. Part of the solution came by the development of the revascularization. There is now growing evidence showing no superiority of angioplasty over medical treatment on cardiovascular events and mortality, renal function and blood pressure control. Hence, RAS blockers resurfaced based on their proven beneficial effects on blood pressure control and cardiovascular prevention in high risk atherosclerotic patients. Thus, RAS blockers belong today to the standard treatment of hypertensive patients with ARAS. However they were not systematically prescribed in trials focusing on ARAS. The ongoing CORAL trial will give us further information on the place of this class of antihypertensive drugs in patients with ARAS.

Disruption of Transitional Stages in 24-h Blood Pressure Recording in Renal Transplant Recipients

Patients with kidney replacement exhibit disrupted circadian rhythms. Most studies measuring blood pressure use the dipper/non-dipper classification, which does not consider analysis of transitional stages between low and high blood pressure, confidence intervals nor shifts in the time of peak, while assuming subjective onsets of night and day phases. In order to better understand the nature of daily variation of blood pressure in these patients, we analyzed 24 h recordings from 41 renal transplant recipients using the non-symmetrical double-logistic fitting assessment which does not assume abruptness nor symmetry in ascending and descending stages of the blood pressure profile, and a cosine best-fitting regression method (Cosinor). Compared with matched controls, double-logistic fitting showed that the times for most transitional stages (ascending systolic and descending systolic, diastolic, and mean arterial pressure) had a wider distribution along the 24-h. The proportion of individuals without daily blood pressure rhythm in the transplanted group was larger only for systolic arterial pressure, and the amplitude showed no significant difference. Furthermore, the transplant recipient group had a less pronounced slope in descending systolic and ascending mean blood pressure. Cosinor analysis confirmed this phase-related changes, showing a wider distribution of times of peak (acrophases). We conclude that daily disruptions in renal transplant recipients can be explained not necessarily by an absence in diurnal variation, but also by changes in waveform-related parameters of the rhythm, and that alterations in the phase of the rhythm are the most consistent finding in these patients.

Current approaches to renovascular hypertension

This article examines the status regarding prevalence, mechanisms, clinical manifestations and management of renovascular hypertension at this point in time. It should be viewed as a work in progress. As with most complex conditions, clinicians must integrate the results of published literature studies while considering each patient's specific features and comorbid disease risks. Beyond identifying renovascular disease as a cause of secondary hypertension, one must manage renal artery stenosis (RAS) itself as an atherosclerotic vascular complication. This disease warrants follow-up regarding progression and potential for ischemic tissue injury. These elements often determine the role and timing for revascularization. In this respect, atherosclerotic renal artery stenosis is analogous to progressive carotid or aortic aneurysmal disease.

[Hypertension in patients with renal artery stenosis]

Renal artery stenosis (RAS) is often present in patients with severe hypertension and atherosclerotic vascular disease. In this setting it is important to screen patients for renovascular disease, e.g. with Duplex-ultrasound, CT- or MR-angiography. The challenge of treating these patients is to find the evidence proving that the RAS is responsible for hypertension and/or renal dysfunction. Measurement of the intra-arterial pressure gradient is necessary in order to determine hemodynamic relevance. On the other side, in these patients hypertension is often of primary and/or renoparenchymatous origin and is aggravated by a renovascular disease. This explains why hypertension cannot be cured even if a high grade stenosis has been removed. In addition, thromb- and cholesterol-embolic material is often mobilized during an invasive procedure and leads to renaparenchymatous ischemia which sustains hypertension after intervention. An individual evaluation of profit versus risk is important for the decision for or against an invasive procedure, especially since there is no sufficient evidence for a decrease of mortality after interventions of RAS. The optimal conservative treatment, including the treatment of atherosclerotic risk factors is recommended.

[Abdominal aortic aneurysm and renovascular disease]

Recent technological advances in the diagnosis and therapy of abdominal aortic aneurysm and renovascular disease are continuing to bring about changes in the way patients suffering from these conditions are treated. The prevalence of both these conditions is increasing. This is due to greater life-expectancy in patients with arteriosclerosis, a pathogenetic factor underlying both conditions. The application of diagnostic imaging techniques to non-vascular conditions has led to the early diagnosis of abdominal aortic aneurysm. Clinical suspicion of reno-vascular disease can be confirmed easily using high-resolution diagnostic imaging modalities such as CT angiography and magnetic resonance angiography. Endovascular intervention is successfully replacing conventional surgical repair techniques, with the result that it may be possible to improve outcome in both conditions using effective and minimally invasive approaches. Future technological developments will enable these endovascular techniques to be applied in the large majority of patients with abdominal aortic aneurysm or renovascular disease.

Renovascular hypertension update

Hypertension detected in patients with renovascular disease poses a major clinical challenge. The rapid expansion of noninvasive imaging, effective antihypertensive drug therapy, and endovascular interventional procedures combine to make optimal management a moving target. Renal arterial disease accelerates the development of hypertension associated with activation of multiple pressor systems and accelerated target organ injury. Younger individuals with fibromuscular lesions often respond well to renal revascularization with minor associated risks. Care must be taken in cases of complex vascular anomalies, such as renal artery aneurysms. Atherosclerotic renal artery stenosis is detected more commonly than ever before and affects more than 85% of patients referred for revascularization. Most are older patients with long-standing hypertension, diabetes, and pre-existing complications of vascular disease. The benefits of extensive workup and intervention in this group of patients are controversial. Antihypertensive drug therapy is most effectively achieved with drugs that block the renin-angiotensin system, but most require multiple agents. Selection of patients for renal revascularization in this group is far more controversial than with fibromuscular disease. Several small trials failed to identify major benefits with renal artery angioplasty as compared to closely monitored drug therapy, although crossover rates from medical to interventional arms were high. The Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) seeks to randomly assign subjects with proven, high-grade renal artery lesions to optimal medical management with and without stenting. This important trial employs distal embolic protection to prevent deterioration of renal function. Understanding the optimal role for renal revascularization depends heavily upon the successful conduct of such trials.

Renovascular Hypertension: Current Concepts

Hypertension produced by renal artery occlusive disease is an important secondary form of hypertension. Clinicians commonly encounter forms of renal arterial disease of varying severity, many of which are of little hemodynamic significance when first detected. Experimental studies emphasize that transient activation of the renin-angiotensin-aldosterone system is necessary for initiation of renovascular hypertension. At some point, angiotensin II activates additional mechanisms responsible for sustained increased blood pressure including sodium retention, endothelial dysfunction, and vasoconstriction related to production of reactive oxygen species. Widespread application of agents that block the renin-angiotensin system, including angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers, render many patients with unilateral renal arterial disease manageable primarily by medical means for many years. In the setting of high a priori likelihood of renovascular disease, recognizing the potential for disease progression during medical therapy and individually evaluating the risks and benefits of renal revascularization are important tasks. Recent prospective studies show limited, but real, benefit regarding blood pressure control for patients with atherosclerotic disease. Whether earlier renal revascularization offers benefits regarding improved morbidity and mortality from cardiovascular end point reduction is an important question to be addressed in multicenter, prospective, randomized trials. Our paradigm stresses the fact that patients with renovascular hypertension require intensive blood pressure control and cardiovascular risk factor intervention, both before and after revascularization. Hence, management of such patients requires close attention and periodic review regarding restenosis and progression of vascular disease.