Nighttime Blood Pressure and New-Onset Left Ventricular Hypertrophy

Abstract

Extensive echocardiographic investigations performed in the past 3 decades have shown that hypertensive heart disease includes a variety of anatomic and functional alterations, such as left ventricular hypertrophy (LVH), systolic/diastolic dysfunction, myocardial fibrosis, and left atrial and aortic dilatations. [1][2][3][4][5] Among these manifestations of cardiac damage, particular attention has been devoted to LVH because this phenotype has been reported to be a powerful, independent predictor of cardiovascular (CV) events and all-cause mortality either in the general population or in hypertensive cohorts. 6,7 Although the pathogenesis of hypertensive LVH is not fully understood, a consistent body of evidence indicates that the severity of pressure overload, as better reflected by out-of-office than by in-office blood pressure (BP) levels, in combination with nonhemodynamic variables, including genetic, ethnic, and humoral factors, plays a pivotal role in its development. 8,9 Nonetheless, numerous reports have also shown that circadian variations in BP correlate to LVH independently of 24-hour ambulatory BP monitoring (ABPM) values. Furthermore, earlier studies suggested that daytime BP, in particular BP values recorded during working hours, is more closely associated with LVH compared with nighttime BP. 10 More recently, however, numerous studies have shown that nighttime BP and nocturnal BP fall are stronger correlates of LVH than daytime or average 24-hour BP. 11,12Although a blunted decrease in nighttime BP (ie, nondipping status) has been associated with unhealthy conditions, including diabetes mellitus, metabolic syndrome, sleep apnea, cardiac or extracardiac organ damage, resistant hypertension, and an increased risk of CV morbidity and mortality, 13-15 this issue remains a source of debate. It is worthy of mention that a systematic review by Hansen et al 16 which included 25 856 hypertensive patients and 9641 individuals randomly recruited from the population revealed that nondipping status and increased night-to-day BP ratio were associated with higher all-cause mortality and CV events but added a marginal prognostic value over and beyond 24-hour BP.

Cardiac Organ Damage and Arterial Stiffness in Autonomic Failure

“…Nighttime BP, in particular systolic values, has been described as an independent predictor of new-onset LV hypertrophy in the general population. 27 In animal models of sinoaortic denervation, characterized by normal BP values and high BP variability, the activation of different mechanosensitive and autocrine pathways mediates cardiac hypertrophy in response to mechanical stress. 28 In our study, LVMi was related to mean 24-hour BP values, and both 24-hour and nighttime SBP were predictors of organ damage in the whole study population independent of indexes of BP variability.…”

“…Se ha comunicado que la PA nocturna, en particular los valores sistólicos, es un factor predictivo independiente de aparición de hipertrofia VI en la población general. 27 En modelos animales de desnervación sinoauricular, caracterizada por valores de PA normales y alta variabilidad de la PA, la activación de diferentes vías mecanosensitivas y autocrinas media la hipertrofia cardíaca en respuesta a esfuerzo mecánico. 28 En nuestro estudio, la MVIi se relacionó con los valores medios de PA de 24 horas, y tanto la PAS de 24 horas como la PAS nocturna fueron factores predictivos de lesión orgánica en toda la población de estudio, independientemente de los índices de variabilidad de la PA. Estos resultados avalan la hipótesis de que, en la INV, la relación entre PAS de 24 horas y MVIi no depende de la variabilidad de la PA, lo que coincide con un estudio previo.…”

Nondipping pattern and carotid atherosclerosis

“…A blunted, or absent, nocturnal fall in BP, reflecting a disrupt circadian rhythm, is considered a powerful risk factor for asymptomatic organ damage and cardiovascular events in a variety of clinical settings; nocturnal BP has been also shown to be a better predictor of cardiovascular events than 24 h or daytime BP [12][13][14].…”

Antihypertensive treatment decreases arterial stiffness at night but not during the day. Results from the Hypertension in the Very Elderly Trial

“…With respect to BP, a recent meta-analysis concluded that a higher nighttime BP is a better predictor for adverse outcome than a higher day-time BP or even a low day-night BP ratio. [15] Specifically a high night-time BP rather than day-time BP is associated with chronic kidney disease, [16] left ventricular hypertrophy [17] and cardiovascular disease. [18][19][20] Cuspidi and Grassi [21] conclude that nocturnal BP should be targeted by treatment.…”