Left ventricular hypertrophy and renal dysfunction during antihypertensive treatment adversely affect cardiovascular prognosis in hypertensive patients

Targeting subclinical organ damage in obstructive sleep apnea: a narrative review

Subclinical abnormalities in cardiac and vascular structure reflect the adverse effects triggered by a variety of risk factors on the cardiovascular (CV) system thereby representing an intermediate step in the cardiovascular continuum; such alterations are recognized as reliable markers of increased cardiovascular risk in different clinical settings including obstructive sleep apnea (OSA). The mechanisms underlying subclinical organ damage (OD) in the OSA setting are multifactorial. Hypoxemia and hypercapnia, induced by repeated collapses of upper airways, have been suggested to trigger a cascade of events such as activation of the sympathetic tone, renin-angiotensin-aldosterone system leading to endothelial dysfunction, vasoconstriction, myocardial and vascular remodeling, and hypertension. Furthermore, coexisting non-haemodynamic alterations such as increased oxidative stress, release of inflammatory substances, enhanced lipolysis and insulin resistance have been reported to play a role in the pathogenesis of both cardiac and extra-cardiac OD. In this article we reviewed available evidence on the association between OSA and subclinical cardiac (i.e., left and right ventricular hypertrophy, left atrial dilatation) and extra-cardiac organ damage (i.e., carotid atherosclerosis, arterial stiffness, microvascular retinal changes, and microalbuminuria). This association is apparently stronger for cardiac and carotid subclinical damage than for other markers (i.e., arterial stiffness and retinal changes) and mostly evident in the setting of severe OSA.

Controversies in the management of the haemodialysis-related arteriovenous fistula following kidney transplantation

Arteriovenous fistula (AVF) is regarded as the best vascular access for chronic haemodialysis (HD). Still, AVF inherently causes significant haemodynamic changes. Although the necessity for vascular access despite its putative cardiovascular complications favours AVF creation in patients under chronic HD, one may question whether sustaining a functional AVF after successful kidney transplantation extends the haemodynamic threat. Small prospective series suggest that AVF ligation causes rapid and sustained reduction in left ventricular hypertrophy. Still, the benefits of such a cardiac remodelling in long-terms of cardiovascular morbi-mortality still need to be proven. Furthermore, the elevation of diastolic blood pressure and arterial stiffness caused by AVF ligation may blunt the expected cardio-protection. Finally, the closure of a functioning AVF may accelerate the decline of kidney graft function. As a whole, the current management of a functioning AVF in kidney transplant recipients remains controversial and does not rely on strong evidence-based data. The individual risk of graft dysfunction and a return to chronic HD also needs to be balanced. Careful pre-operative functional assessments, including cardio-pulmonary testing and estimated glomerular filtration rate slope estimation, may help better selection of who might benefit the most from AVF closure. Large-scale prospective, ideally multi-centric, trials are essentially needed.

Prognostic value of combined target-organ damage in patients with essential hypertension

BACKGROUND

Whether the combination of chronic kidney disease (CKD) and left ventricular hypertrophy (LVH) affects the cardiovascular (CV) risk in patients with uncomplicated hypertension is poorly investigated. The aim of this study was to assess the effects of LVH, CKD, and their combination on CV events in hypertension.

METHODS

This study analyzed 1,078 patients with essential hypertension.

RESULTS

LVH was present in 104 (9.6%) patients, CKD was present in 556 (51.5%) patients, and the combination of LVH and CKD was found in 174 (16.1%) patients. During the follow-up (median = 84 months), 52 CV events were observed (0.64 events/100 patient-years): 6 (2.4%) in patients without target-organ damage (TOD), 6 (5.7%) in patients with LVH, 20 (3.6%) in patients with CKD, and 20 (11.4%) in patients with combined LVH+CKD. Adjusted hazard ratio (HR) for CV events was 1.62 (P = 0.34) for LVH, 0.951 (P = 0.94) for CKD, and 2.45 (P = 0.03) for LVH+CKD. After multivariable Cox proportional hazard analysis, the combination of LVH+CKD was significantly associated with risk of CV events, when the model was adjusted for sex and age (HR = 2.447; P = 0.03) and for the presence of 1 CV risk factor (HR = 3.226; P = 0.02). In contrast, the association of LVH+CKD was no longer significant when the model was adjusted for sex, age, and the presence of ≥ 2 CV risk factors.

CONCLUSIONS

The results of this study highlight the relevance of the interactions between TODs and hemodynamic, anthropometric, and metabolic abnormalities in the CV risk stratification of patients with essential hypertension.

Myocardial perfusion imaging for predicting cardiac events in Japanese patients with advanced chronic kidney disease: 1-year interim report of the J-ACCESS 3 investigation

PURPOSE

Whether myocardial perfusion imaging (MPI) can predict cardiac events in patients with advanced conservative chronic kidney disease (CKD) remains unclear.

METHODS

The present multicenter prospective cohort study aimed to clarify the ability of MPI to predict cardiac events in 529 patients with CKD and estimated glomerular filtration rates (eGFR) < 50 ml/min per 1.73(2) without a definitive diagnosis of coronary artery disease. All patients were assessed by stress-rest MPI with (99m)Tc-tetrofosmin and analyzed using summed defect scores and QGS software. Cardiac events were analyzed 1 year after registration.

RESULTS

Myocardial perfusion abnormalities defined as summed stress score (SSS) ≥4 and ≥8 were identified in 19 and 7 % of patients, respectively. At the end of the 1-year follow-up, 33 (6.2 %) cardiac events had occurred that included cardiac death, sudden death, nonfatal myocardial infarction, and hospitalization due to heart failure. The event-free rates at that time were 0.95, 0.90, and 0.81 for groups with SSS 0-3, 4-7, and ≥8, respectively (p = 0.0009). Thus, patients with abnormal SSS had a higher incidence of cardiac events. Multivariate Cox regression analysis showed that SSS significantly impacts the prediction of cardiac events independently of eGFR and left ventricular ejection fraction.

CONCLUSION

MPI would be useful to stratify patients with advanced conservative CKD who are at high risk of cardiac events without adversely affecting damaged kidneys.

Preclinical cardiorenal interrelationships in essential hypertension

A diseased heart causes numerous adverse effects on kidney function, and vice versa renal disease can significantly impair cardiac function. Beyond these heart-kidney interrelationships at the clinical level, a reciprocal association has been suggested to exist even in the early stages of those organs' dysfunction. The aim of the present review is to provide evidence of the presence of a preclinical cardiorenal syndrome in the particular setting of essential hypertension, focusing on the subsequent hypertensive sequelae on heart and kidneys. In particular, a plethora of studies have demonstrated not only the predictive role of kidney damage, as expressed by either decreased glomerular filtration or increased urine albumin excretion, for adverse left ventricular functional and structural adaptations but also preclinical heart disease, i.e. left ventricular hypertrophy that is associated with deterioration of renal function. Notably, these reciprocal interactions seem to exist even at the level of microcirculation, since both coronary flow reserve and renal hemodynamics are strongly related with clinical and preclinical renal and cardiac damage, respectively. In this preclinical setting, common pathophysiological denominators, including the increased hemodynamic load, sympathetic and renin-angiotensin system overactivity, increased subclinical inflammatory reaction, and endothelial dysfunction, account not only for the reported associations between overt cardiac and renal damage but also for the parallel changes that occur in coronary and renal microcirculation.