Determinants of isolated systolic hypertension in the elderly

W W Nichols1, F A Nicolini, C J Pepine

  • 1Department of Medicine/Cardiology, University of Florida, Gainesville 32610.

Insights

Isolated systolic hypertension in the elderly is driven by increased arterial stiffness and reduced peripheral vascular bed area. These factors lead to higher pulse wave velocity and augmented systolic pressure due to early wave reflection.

Area of Science:

  • Cardiovascular Physiology
  • Geriatric Medicine
  • Biomedical Engineering

Background:

  • Isolated systolic hypertension (ISH) is common in the elderly.
  • Understanding its underlying mechanisms is crucial for effective management.

Purpose of the Study:

  • To investigate the determinants of isolated systolic hypertension in elderly individuals.
  • To analyze the contributions of arterial stiffness and vascular resistance to ISH.

Main Methods:

  • Measured pulsatile blood pressure and flow in the ascending aorta using a multisensor catheter.
  • Calculated impedance spectra in 18 subjects undergoing cardiac catheterization.
  • Compared 9 subjects with ISH to 9 age-matched normotensive controls.

Main Results:

  • Subjects with ISH exhibited significantly higher peripheral vascular resistance (44%) and aortic stiffness (107%) compared to controls.
  • Characteristic impedance and wave reflection components of aortic input impedance were elevated in the ISH group.
  • Increased pulse wave velocity and earlier return of pulse wave reflection in systole were observed in ISH patients.

Conclusions:

  • Reduced peripheral vascular bed area and increased aortic stiffness contribute to ISH.
  • Arterial stiffness in ISH offsets potential increases in diastolic blood pressure from elevated peripheral resistance.
  • Early return of reflected pressure waves augments systolic pressure, explaining the elevated systolic and pulse pressure in ISH.
Abstract

Related Concept Videos

Factors affecting Blood pressure01:28

Factors affecting Blood pressure

Several physiological and lifestyle factors influence blood pressure (BP). Understanding these factors is crucial as they are significant in patient education and blood pressure management.
Physiological Factors:
Hypertension and Regulation of Blood Pressure01:18

Hypertension and Regulation of Blood Pressure

Hypertension, the most common cardiovascular disease, is diagnosed through repeated measurements of elevated blood pressure. Its risks, including damage to the kidney, heart, and brain, are directly proportional to blood pressure levels. Starting from 115/75 mm Hg, the risk of cardiovascular disease doubles with each increment of 20/10 mm Hg. The diagnosis relies on blood pressure measurements, not on patient symptoms, as hypertension is often asymptomatic until end-organ damage is imminent or...
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Excretion01:18

Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Excretion

In geriatric patients, renal physiology undergoes significant changes, including diminished renal blood flow and a lower glomerular filtration rate (GFR), leading to alterations in medication clearance. Drugs such as aminoglycoside antibiotics, lithium, and digoxin, which rely on glomerular filtration for removal from the body, particularly impact pharmacokinetics. These drugs tend to have slower clearance rates in older adults, necessitating careful dosage considerations.Evaluation of renal...
Hypertension I: Introduction01:28

Hypertension I: Introduction

Hypertension is a widespread, long-term medical condition where blood pressure in the arteries remains elevated. It is characterized by systolic blood pressure readings of 130 mm Hg or above or diastolic blood pressure (DBP) readings of 80 mm Hg or higher. Unmanaged hypertension poses significant health risks, making the distinction between primary (or essential) hypertension and secondary hypertension crucial, as their management and implications vary.Primary HypertensionPrimary hypertension,...
Hypertension II: Pathophysiology01:29

Hypertension II: Pathophysiology

Hypertension is a chronic condition in which the blood's force against artery walls is excessively high, posing risks such as heart disease. The condition's underlying mechanisms involve complex interactions among the cardiovascular, kidney, and autonomic nervous systems.Renin-Angiotensin-Aldosterone System (RAAS): This system significantly influences blood pressure regulation. When blood pressure decreases, the kidneys secrete renin. This enzyme transforms angiotensinogen, a plasma protein,...
Hypertension III: Clinical Manifestations and Diagnostic Studies01:30

Hypertension III: Clinical Manifestations and Diagnostic Studies

Hypertension is asymptomatic and also referred to as the "silent killer" until it progresses to a severe stage or causes target organ disease. Patients may experience symptoms stemming from the strain on blood vessels and tissues in various organs or the heart's increased workload.Physical exams might show no abnormalities other than high blood pressure. Signs of vascular damage, when present, correspond to the organs supplied by the affected vessels, leading to target organ damage. For...