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Although resting hemodynamic load has been extensively investigated as a determinant of left ventricular (LV) hypertrophy, little is known about the relationship between provoked hemodynamic load and the risk of LV hypertrophy. We studied central pressure-flow relations among 40 hypertensive and 19 normotensive adults using carotid applanation tonometry and Doppler echocardiography at rest and during a 40% maximal voluntary forearm contraction (handgrip) maneuver. Carotid-femoral pulse wave velocity (CF-PWV) was measured at rest. Hypertensive subjects demonstrated various abnormalities in resting and induced pulsatile load. Isometric exercise significantly increased systemic vascular resistance, aortic characteristic impedance (Zc), induced earlier wave reflections, increased augmentation index, and decreased total arterial compliance (TAC; all P [less than or equal to] 0.01). In hypertensive subjects, CF-PWV was the strongest resting predictor of LV mass index (LVMI) and remained an independent predictor after adjustment for age, gender, systemic vascular resistance, reflection magnitude, aortic Zc, and TAC ([beta] = 2.52 m/s; P < 0.0001). Age, sex, CF-PWV, and resting hemodynamic indexes explained 48% of the interindividual variability in LVMI. In stepwise regression, TAC ([beta] = -17.85; P < 0.0001) during handgrip, Zc during handgrip ([beta] = -150; P < 0.0001), and the change in the timing of wave reflections during handgrip ([beta] = -0.63; P = 0.03) were independent predictors of LVMI. A model that included indexes of provoked hemodynamic load explained 68% of the interindividual variability in LVMI. Hemodynamic load provoked by isometric exercise strongly predicts LVMI in hypertension. The magnitude of this association is far greater than for resting hemodynamic load, suggesting that provoked testing captures important arterial properties that are not apparent at rest and is advantageous to assess dynamic arterial load in hypertension. arterial load; arterial compliance; wave reflections; aortic stiffness doi: 10.1152/ajpheart.00334.2009

Objectives: Out‐of‐hospital cardiac arrest (OHCA) afflicts >350,000 people annually in the United States. While postarrest coronary angiography (CAG) with percutaneous coronary intervention (PCI) has been associated with improved survival in observational cohorts, substantial uncertainty exists regarding patient selection for postarrest CAG. We tested the hypothesis that symptoms consistent with acute coronary syndrome (ACS), including chest discomfort, prior to OHCAs are associated with significant coronary lesions identified on postarrest CAG. Methods: We conducted a multicenter retrospective cohort study among eight regional hospitals. Adult patients who experienced atraumatic OHCA with successful initial resuscitation and subsequent CAG between January 2015 and December 2019 were included. We collected data on prehospital documentation of potential ACS symptoms prior to OHCA as well as clinical factors readily available during postarrest care. The primary outcome in multivariable regression modeling was the presence of significant coronary lesions (defined as >50% stenosis of left main or >75% stenosis of other coronary arteries). Results: Four‐hundred patients were included. Median (interquartile range) age was 59 (51–69) years; 31% were female. At least one significant stenosis was found in 62%, of whom 71% received PCI. Clinical factors independently associated with a significant lesion included a history of myocardial infarction (adjusted odds ratio [aOR] = 6.5, [95% confidence interval {CI} = 1.3 to 32.4], p = 0.02), prearrest chest discomfort (aOR = 4.8 [95% CI = 2.1 to 11.8], p ≤ 0.001), ST‐segment elevations (aOR = 3.2 [95% CI = 1.7 to 6.3], p < 0.001), and an initial shockable rhythm (aOR = 1.9 [95% CI = 1.0 to 3.4], p = 0.05). Conclusions: Among survivors of OHCA receiving CAG, history of prearrest chest discomfort was significantly and independently associated with significant coronary artery lesions on postarrest CAG. This suggests that we may be able to use prearrest symptoms to better risk stratify patients following OHCA to decide who will benefit from invasive angiography. [ABSTRACT FROM AUTHOR]