Coronary Heart Disease

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Coronary Heart DiseaseCoronary Artery Disease

• Ryan Davis, Talia Vernamonti, Ray Horchuck

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• Systolic Blood Pressure During Recovery From
  Exercise and the Risk of Acute Myocardial
  Infarction in Middle-Aged Men
• Jari A. LaukkanenJukka T. Salonen
• Hypertension
• Vol44 December 2004
• Pgs 820-824

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• Introduction
• An exercise-induced rise in SBP has been found to
  be a predictor of future hypertension, left
  ventricular hypertrophy, stroke, and
  cardiovascular disease (CVD) mortality in
  apparently healthy people.
• An abnormal delay in the decrease in HR after
  exercise is suggested because of inadequate
  reaction of vagal tone resulting from an increase
  in activity of the sympathetic nervous system.
• The study investigated the prognostic
  significance of SBP response after a standardized
  cycle ergometer exercise test with regard to risk
  of future AMI in a population-based sample of
  men.

• Methods
• For 605 men (25.9) examined, the testing
  protocol comprised 3-minute warm-up at 50 W
  followed by a step-by-step gradual increase in
  workload by 20 W per minute.
• The remaining 1731 men (74.1) were tested with a
  linear increase in the workload at 20 W per
  minute.
• There was an ECG that registered continuously
  during the test.
• Maximal oxygen uptake (VO2max) was defined as the
  highest value or the plateau of directly measured
  oxygen consumption using a respiratory gas
  analyzer.

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Continued

• Maximal oxygen uptake (VO2max) was defined as the
  highest value or the plateau of directly measured
  oxygen consumption using a respiratory gas
  analyzer.
• During the symptom-limited exercise test, an
  average maximal HR during exercise was 155 bpm.
• Mean maximal SBP and SBP at 2 minutes after
  exercise were 202 mm Hg and 183 mm Hg,
  respectively.
• A total of 358 AMIs (acute myocardial infarction)
  occurred during an average follow-up period of
  13.1 years.
• VO2max, SBP after exercise, and exercise-induced
  myocardial ischemia were significant predictors
  measured during the exercise test.

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Continued

• Conclusion/Summary
• In this study, exercise test predictors including
  exercise capacity, maximal HR and SBP after
  exercise were significant predictors for AMI.
• It has been suggested previously that abnormal
  SBP response is an important indicator for
  coronary artery disease not only during exercise
  but also during the recovery phase.
• The article concludes that SBP as a result of
  exercise has a reasonable effect on AMIs in CHD
  depending on the reaction of the SBP. It also
  concludes that an increased VO2max shows a
  decrease in the prevalence of CHD.

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• Peripheral Arterial Responses to Treadmill
  Exercise AmongHealthy Subjects and
  Atherosclerotic Patients
• Alan Rozanski Mara Bauman
• Circulation
• Vol103 January 2001
• Pages 2084-2089

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Continued

• This study compared finger pulse-wave amplitude
  (PWA) responses to exercise among 50 normal
  volunteers and 57 patients with
• atherosclerotic coronary artery disease (CAD).
• PWA (pulse-wave amplitude) was quantified for
  each minute of exercise as a ratio relative to
  baseline.
• Exercise Protocol
• The Bruce exercise protocol was performed in a
  thermo neutral environment (21C).
• Patients exercised to exhaustion, unless severe
  chest pain or hypotension intervened.

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Continued

• Fifty healthy volunteers, without known
  illnesses, were recruited to assess the effects
  of exercise on finger blood flow.
• A total of 57 patients had significant coronary
  atherosclerosis, 38 had prior myocardial
  infarction, and 43 had undergone a prior coronary
  revascularization procedure.

• Pulsatile blood volume responses were assessed by
  peripheral arterial tonometry using a
  plethysmographic device.
• Finger pulse-wave measurements were obtained
  continuously by having the subjects leaning the
  forearm of the monitored hand lightly on a padded
  supporting device attached to the treadmills
  side rail to minimize free hand movement

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Continued

• Exercise duration for the Bruce protocol lasted
  for about 9.6 mins in patients who were free of
  disease.
• Exercise testing for those who were clinically
  diagnosed with CAD lasted about 8.2 mins.
• 2 PWA patterns were noticed in disease free
  patients 76 noted a rise in PWA during exercise
  and 24 had a fall in PWA below the baseline
  value at or before the end of exercise after an
  initial rise.

• 3 PWA patterns were noticed in CAD patients.
• (1)47 noted a rise in PWA during exercise.
• (2)18 showed an initial rise followed by a fall
  before the end of exercise.
• (3)35 showed a fall after the onset of exercise
  with a progressive decline during the exercise
  bout.

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Continued

• Since PWA is measuring a blood flow in the finger
  or toe (in the cutaneous bed), it should
  replicate the amount of blood flow in arterial
  regions.
• The results of this test indicate that 33 of
  CAD patients manifested a fall in PWA from the
  onset of exercise which means these patients have
  a constricted blood flow during exercise.
• These falls in PWA were not noted among the
  healthy individuals who were a part of this
  exercise protocol.
• Other CAD patients manifested falls in PWA that
  began at much lower heart rate thresholds as
  compared to the healthy individuals.
• Please Note some CAD participants were on
  medications such as beta blockers, ACE inhibitors
  or calcium blockers which would have an affect on
  heart rate during exercise.

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Conclusion

• This study shows us that people with CAD when in
  correlation with
• PWA and blood volume, have a lower blood volume
  and VO2max
• than those without the presence of CAD. Also,
  the achieved
• metabolic equivalent level was lower among CAD
  patients who showed vasoconstriction which says
  the study may indicate that such
  vasoconstrictions may be due to low exercise
  efficiency.

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• Exercise Training Improves Overall Physical
  Fitness and Quality of Life in Older Women With
  Coronary Artery Disease
• Hung, ChihyaMark Haykowsky
• American College of Chest Physicians
• Vol126 April 2004
• Pages 1026-1030

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Continued

• Background
• Older woman with CAD may have the most to gain
  from exercise in a rehabilitation program. This
  is because they have a peak VO2 that is 26 to 45
  lower than age matched healthy sedentary or
  active women.
• Older women with coronary artery disease have
  reduced peak aerobic power, muscle strength, and
  quality of life. Exercise can improve all these
  areas that were previously mentioned.

• The study compared the effect of aerobic training
  or combined aerobic and strength training on VO2
  peak, distance walked in 6 min, upper and lower
  extremity maximal strength, quality of life in 18
  women (ages range from 60 80 years old)
  documented with CAD.

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Continued

• Methods
• After baseline testing, subject were randomly
  placed into an aerobic testing group or a a
  combined aerobic and strength group (treadmill
  and cycle exercise plus upper and lower extremity
  strength training. Each group exercised 3
  days/week for 8 weeks.
• Results
• Both groups increased their VO2 peak, distance
  walked in 6 min, lower extremity strength, and
  emotional and global quality of life. The
  combined group of aerobic and strength training
  patients also improved upper extremity strength
  and physical and social quality of life this
  factor was unchanged in the aerobic group.

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• Exercise and Physical Activity in the Prevention
  and Treatment of Atherosclerotic Cardiovascular
  Disease
• Paul D. ThompsonNanette K. Wagner
• Circulation
• Vol107 June 2003
• Pages 3109-3116

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• Introduction
• Habitual physical activity also prevents the
  development of coronary artery disease (CAD) and
  reduces symptoms in patients with established
  cardiovascular disease.
• This statement focuses on aerobic physical
  activity and does not directly evaluate
  resistance exercises.
• Most of the research linking physical activity
  and cardiovascular disease has evaluated aerobic
  activity.

• Methods
• At least 44 randomized controlled trials
  including 2674 participants have studied the
  effect of exercise training on resting blood
  pressure.
• The average reduction in systolic and diastolic
  blood pressure was 3.4 and 2.4 mm Hg,
  respectively.
• Baseline blood pressure was an important
  determinant of the exercise effect.

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Continued

• Results
• Data demonstrates a graded relationship of
  decreasing CAD rates with increasing levels of
  activity.
• The magnitude of the exercise effect is
  influenced by characteristics of the exercise
  intervention, individual variation, and whether
  exercise produces concomitant reductions in body
  weight.

• Conclusion
• Health professionals should personally engage in
  an active lifestyle to familiarize themselves
  with the issues involved in maintaining lifelong
  physical activity. Sedentary lifestyles have a
  high correlation with Coronary Artery Disease and
  Coronary Artery Disease which is why we as health
  promotion specialists should encourage more
  physical activity among children, adults, and
  elderly.

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• Impaired Heart Rate Response to Graded Exercise
• Michael S. LauerDaniel Levy
• Circulation
• Vol93 1996
• Pages 1520-1526

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Continued

• Introduction
• Reports have suggested that an attenuated
  exercise heart rate response may be associated
  with coronary heart disease risk and with
  mortality.
• This investigation was designed to look at the
  predictive implications of exercise heart rate
  response in a population-based sample.

• Methods
• 1575 male participants who were free of coronary
  heart disease, who were not taking ß-blockers,
  and who underwent submaximal treadmill exercise
  testing (Bruce protocol) were studied. Heart
  rate response was assessed in three ways.
• 1. Failure to reach 85 of HR max
• 2. Increase in heart rate from rest to peak
  exercise
• 3. The ratio of heart rate to metabolic reserve
  used by stage 2 of exercise

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Continued

• Results
• Failure to achieve target heart rate remained
  predictive of incident coronary heart disease
  even after adjusting for age.
• The increase in exercise heart rate remained
  inversely predictive of total mortality and
  coronary heart disease incidence.
• Conclusion
• Regular physical activity using large muscle
  groups produces cardiovascular adaptations that
  increase exercise capacity, endurance, and
  skeletal muscle strength.
• An attenuated heart rate response to exercise, a
  manifestation of chronotropic incompetence, is
  predictive of increased mortality and coronary
  heart disease incidence.

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Final Thought

• Higher Quality of Life
• I hope that through this presentation and
  research, people will understand that physical
  activity is vital for a higher quality of life.
  Numerous studies have shown that a sedentary
  lifestyle is linked to coronary heart disease and
  morbidity among adults. Studies have also showed
  us that a sedentary lifestyle is also linked to a
  number of other diseases such as hypertension,
  hypercholesterolemia, stroke, obesity, and
  diabetes. As a final thought, exercise is the
  key to a healthier and higher quality of life
  among healthy and unhealthy individuals.