SCIENCE &THE NEW ERA OF CARDIAC REHABILITATION

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 INTRODUCTION

This is a slightly revised version of a talk first given by Phil Harris to Berwick Area Heart Support Group November 2003. This page was updated December 2004

There was very little cardiac rehab around when I had my MI nearly 14 years ago, and there were no statins on offer either. Encouraging reports have emerged over the last 10 years, particularly in the last 3 years, and even in the last 3 months, concerning the benefits that can be obtained from both lifestyle change and modern medication. In my scene setting for the talk I made the point that not everybody gets coronary (CAD) or other arterial disease. There are parts of the world that still show very few cases. In contrast, there are very high incidences in the industrialised countries of the ‘West’.

THE BAD NEWS

Recent information suggests that underlying arterial disease is even more common than we imagined in ‘Western’ countries. Examination of people who died for other reasons has revealed that many of them had at least some ‘atheroma’ or ‘plaque’ in the walls of their heart arteries. The suggestion is now that perhaps 70% of us have some atheroma by the time we are 50, whether or not we have shown symptoms. Similarly, work using the new ultrasound catheter (IVUS), has showed that angiograms only reveal a fraction of most atheromas / plaque, and then only when a plaque has grown sufficiently to begin to block the artery. (Apparently, arteries’ respond to early plaque by expanding to maintain a normal ‘bore’ or inner diameter. An apparently normal looking artery in the angiogram can have walls full of plaque.) We begin to see why heart attacks, (clots that block the blood flow and starve that local part of the heart of oxygen), happen, more often than not, with no warning. A seriously narrowed artery might give us warning angina pain symptoms, but, unfortunately, the potentially deadly clot can happen at any plaque.

 From The Current and Future Outlook for Regression of Atherosclerosis: Next Steps Toward the Horizon by Steven E. Nissen, MD www.medscape.com/viewprogram/2590   http://www.medscape.com/viewarticle/460224_11

THE BETTER NEWS

(lowering risk & reversing atheroma)

Many of us do not get heart attacks, even if we have the underlying arterial disease. Changes in lifestyle can dramatically reduce the risk of heart attack (or comparable “acute event”); for example stopping smoking will lower risks in days. Other information from scientific studies concerning lifestyle is very encouraging, and is listed in this report. Additionally, modern drugs not only provide reductions in risk of heart attack, but also can significantly reduce the underlying plaque in the artery walls. Regression of the disease plaque / atheroma is a distinct possibility. The work of Steven Nissen already quoted, and others, makes it clear that the cholesterol lowering drugs increasingly, and especially in their latest forms, can achieve dramatic changes in the burden of disease in the artery walls. (Recently a press report suggested that the death rate for CAD patients here in Northumberland has gone down 27% in the last 2-3 years, which is apparently due to less smoking & the more uniform prescribing of statins.) The current story is that every little counts. Serious efforts to change smoking, exercise and diet, and to join with others in positive endeavour will, with our medication, not only make us much safer, but also give us the prospect of reducing our disease. There are exciting developments in the wings. Although most of us tolerate statin medication, there are downsides for some, and new medications show promise.

  SOURCES

The studies I used to illustrate the talk and this report are from reputable sources and mostly from the well-known scientific and medical journals. They typically involve scientists employed at Medical University and Government Research Centres in this and other countries. For example: I quote from the leading science journal in the UK, Nature, and The Lancet and the British Journal of Cardiology, as well as the international medical science journals Circulation and Hypertension. Also: there are the Journal of the American Medical Association (JAMA) and, the New England Journal of Medicine, the Journal of the American College of Cardiology, the American Journal of Cardiology, and others of similar high standing. The particular studies that I quote usually represent a tip of a well-constructed pyramid of knowledge.

 DEDICATIONS

There were small pathfinder studies in the early 90s that were encouraging. I dedicated my talk to persons involved in these ground-breaking studies and also to a local healer, Julie Jones, who helped me immensely in the early days.

The study by Dr Ornish in 1990 was small, (20 people + ‘control’ group), but 80% of his treatment group improved their narrowed arteries, and nobody got any worse.(Plaque or ‘lesion’, or atheroma, is an inflamed ‘fibro-proliferative’ patch growing within an artery wall, which can lead to ‘stenosis’ or narrowing of the artery).The group seriously changed their diet, did regular exercise and worked hard at their social / emotional environment. The study doctors used angiograms and the then very new High-Tec ‘PET’ scan to photograph and measure lesions and the flow of blood in the coronary arteries. Follow up after 5 years confirmed these favourable results. Lesions generally continued to get smaller. Subsequent studies, some with very much larger numbers of persons, by other scientists, also have produced very encouraging results, and help give us better explanations of why aspects of the way we live contribute to our disease. Changes in the way we live can contribute to slowing down the progress of arterial disease, and even, for some, can reverse it, while providing protection from symptoms such as angina or heart attack. Ornish,1998; JAMA. 280:2001-2007

Dr Bob Lewin (he later produced our Heart Manual and became Professor of Cardiac Rehabilitation at York University) used a talented Yoga teacher (Brenda Botterill) in Edinburgh in a study designed to improve exercise tolerance in angina patients. Some who had not been able to walk down the road because of disabling pain from constricted blood flow in their coronary arteries, were feeling, 6 months later, the benefit of walking in the Pentland Hills. Lewin,1999; Heart 82:654-655 ( December ). Lewin, 1995; British J. Cardiology 1: 221-226

 Brenda Botterill with Yoga class, Edinburgh 1993

I also dedicated my talk to some of the vast number of animals whose sacrifices contribute to our understanding. I hope always for a more kindly and less invasive science for humans and animals.

Watanabe rabbits. This unfortunate laboratory strain inevitably gets arteriosclerosis, but a favourable social environment slows disease. McCabe, 2002; Circulation 105:354-359

 SCENE SETTING

50% of ALL ‘WESTERN’ DEATHS result from arterial disease, (which is the main cause of Heart Disease, Stroke, & Gangrene of the extremities). “The lesions [plaque] result from an excessive inflammatory fibroproliferative response to various forms of insult to the endothelium and smooth muscle of the artery wall.”- “The earliest [form] is the “fatty streak” [found in] half of the autopsy specimens of children aged 10-14.”               Russell Ross, 1993; Nature 362:801-809

Food and disease in rural Asia compared with 'West’ Nutrient Asian West Total protein (g/day)  64  91 Plant protein (g/day) 53  27 Carbohydrate (g.day) 353 243 Fat (g/day)  43 114 % Calories from fat   10- 15% 43% Dietry fibre (g/day)  45 10 Blood Total Cholesterol range  2.3 - 4.4 mmol/L  4.0 - 7.0 mmol/L For every 100 of us, who get; Heart disease Rural Asia has only 6 Breast cancer Rural Asia has only 20 Colon Cancer Rural Asia has only 33

Table. NOT EVERYBODY GETS ARTERIAL DISEASE (mmol/L TC x 38.6 = mg/dL)  Even among advanced industrial countries (the ‘West’) there are large differences in the numbers. Greece has moved up very recently as it modernised from a traditional Mediterranean farming country. Japan has retained a lot of its traditional patterns

Table. DEATHS FROM CHD PER 100,000; in selected countries

Note that figures are changing. America was seriously reducing heart disease deaths from a huge peak in the early 60s until the recent decade when they may have stalled. Reducing smoking over the last 20 years has made a big difference to CHD mortality in England & Wales (Belgin, 2004; Circulation 109;1101-1107). Northumberland has seen a big decrease in CHD deaths recently. The effect of the improvement from smoking cessation and the very recent widespread use of statins drugs however is likely to be undermined by increasing obesity and diabetes, as appears to be happening in Scotland, (British Heart Foundation Newsletter January 2004). The rest of the world as it develops and adopts ‘western’ lifestyles, particularly diet, is getting rapidly worse. For an interesting lecture focussed on modern Japan try www.pitt.edu/~super1/lecture/lec4091/index.htm

 CLASSIC MAJOR RISK FACTORS

 Risk increases with age

 Table. PERCENTAGE DUE TO HEART DISEASE OF ALL DEATHS BY AGE GROUP

(‘WESTERN’ POPULATIONS

 RISK FACTORS

1.    BLOOD LIPIDS [+ INFLAMMATION] Almost nobody with lifetime cholesterol below 3.9 mmol/L gets artery disease. (Framingham Study). In a recent study of patients with mild coronary arterial disease, CAD, a LDL value of 2.0 mmol/L or below, [achievable with statin medication] predicts, on average, no annual increase in size of arterial lesions. (Clemens von Birgelen, 2003. et al. Circulation. 108:2757.) NOTE that multiplication factor 38.6 converts mmol/L cholesterol to mg/dL (the units used in USA). 3.9mmol/L is approx. equivalent to 150 mg/dL

2. BLOOD PRESSURE

3. WEIGHT

4. DIABETES (middle age) This and glucose intolerance more than doubles risk of CHD acute events. The risk for middle aged women will approach that of men.

5. SMOKING

6. GENES

 CARDIAC REHABILITATION

1. MEDICATION - e.g. STATINS, ASPIRIN [improves blood lipids & inflammation; reduces risk of clotting & all risks; if sufficient reduces plaque]

2. SMOKING [constricts arteries and lowers antioxidants, increases risk of clotting and overall risk]

3. EXERCISE [improves weight, blood pressure, lipids, arterial tone/elasticity, inflammation, blood sugar control, mood, reduces risk]

4. FOOD [depending on type & quantity, for better or worse: weight, blood pressure, lipids, blood sugar control, arterial elasticity, inflammation, antioxidants]

5. STRESS CONTROL – e.g. ‘BREATHING’ [improves exercise tolerance, blood pressure, plaque stability, immune activity, arterial tone, mood]

6. COMBINED PROGRAMME LIFESTYLE & MEDICATION[slows or reverses arterial blockage & ‘calcification’, stabilises existing plaque, seriously reduces all risks]

NOTE THAT OVERLOAD OF THE BODY’S ANTI-OXIDANT DEFENCES shows a marker (8-iso-prostglandinF2) that is strongly associated with Coronary Heart Disease, diabetes mellitus, hypercholesterolemia, hypertension, and smoking. Schwedhelm,2004; Circulation. 109:843-848. See also below: ‘DIET MODIFIES ARTERIAL PERFORMANCE & A COMBINATION OF MAJOR RISK FACTORS’

 RISK FACTOR MODIFICATION

 EXCERCISE

It is surprising how little exercise is needed

Greater leisure-time physical activity in France compared with Northern Ireland, helped explain the fewer cases of CHD / MI in France (exercise proved to be a better explanation than diet of the difference in disease between the countries)                        Wagner, 2002; Circulation. 105:2247-2252.      Sorelle, 2002; Circulation. 105:e9105.

Moderate exercise increases elasticity of arteries and the flow of blood in heart failure & hypertensive and healthy people, Goto, 2003; Circulation.108:530.

 Even 30 to 60 minutes of exercise per week was sufficient to lower blood pressure in hypertensives. Ishikawa-Takata,2003; Am J Hypertens 16:629-633.

20 minutes exercise a day makes big (anti-inflammatory) difference in

Chronic Heart Failure. Gielen,2003; J Am Coll Cardiol. 42:861-871

 Brief 10 min exercise activities are useful if they add up to about 30 min a day              Schmidt, 2001; J Am Coll Nutr 20:494-501.

Moderate exercise should raise your pulse, but not too much Goto, 2003; Circulation. 108:530

Around 60 - 70% of your maximum heart rate is fine: this is about the same as brisk walking or very slow running when you are fit

THE GYM typically tries to reach the ‘training rate’, which is 75% of maximum which is more than you need (80% IS TOO MUCH)

60y old target heart rate (HR) is about 112 (maximum HR is about160-165)

50y old target heart rate is about 122

Exercise helps preserve artery activity as we get older

Exercise preserves baroreflex sensitivity (Hunt, 2001; Circulation. 103:2424-2427)

NOTE, better baroreflex (and heart rate variability) give lower risk after MI                    (La Rovere, 1998; Lancet. 351: 478-484)

 DIET

Diet makes a difference

• over a lifetime
• after a few weeks
• even after a single meal

 DIET MODIFIES RISK FACTORS

 ‘HYPERTENSION & BLOOD LIPIDS’

‘Dietary change’ reduces hypertension and lowers total and LDL cholesterol - ‘DASH’ trial  (Blackburn, 2001; Am J Clin Nutr 74, 1, 1-2.) (Moore, Hypertension 2001 38:155-158.) Compared with ‘moderate’ diet that was 37% of calories as fat (14% calories saturated), DASH diet was:-

• less than half the saturated fat, 
• less than 30% of calories as total fat,
• 3 times fruit, 2 times the veg,
• less than one third the amount of red meat, and less sugar

 ‘DIABETES’

A National Institute for Health (USA) study showed that people who follow a low-fat, low-calorie diet, exercise 30 minutes a day five times a week, have a far smaller risk (reduced by 31%) of developing diabetes than these who don't.                                      Knowler, 2002; N Engl J Med 346:393-403

A recent Finnish study shows dramatic reduction in diabetes risk in patients with already impaired glucose tolerance. Lindstrom, 2003; J Am Soc Nephrol 14:S108-S113.  Each subject received individualised counselling aimed at reducing weight and intake of total and saturated fat, and increasing intake of fibre and physical activity. A follow-up at 3.2 years showed the risk of diabetes was reduced by 58%in the intervention group compared with the control group. The reduction in the incidence of diabetes was directly associated with number and magnitude of lifestyle changes. Subjects reduced weight, exercised more, eat less fatty foods and boosted intake of fibre-rich foods such as fruits, vegetables, oatmeal and bran cereal.

A small study suggests that a providing a higher amount of dietary fiber (particularly the soluble type) improves glycemic control, decreases insulin levels, and decreases plasma lipids in 6 weeks in patients with type 2 diabetes. (Total fiber per day, 50 g; 25 g of soluble fiber and 25 g of insoluble fiber) Chandalia, 2000; N Engl J Med. 342(19): 1392-1398

Changing from white bread to wholemeal bread is suggested (wholemeal bread also has twice the magnesium, which may help).

“White bread was the food most strongly related to diabetes incidence and was also the most strongly associated with GI [glycemic index]. Thus, the simple change from white bread to lower-GI bread within a high-carbohydrate diet could reduce the risk of diabetes.” Hodge, 2004, Diabetes Care 27:2701-2706,

 DIET MODIFIES

 ‘ARTERIAL PERFORMANCE AND A COMBINATION OF MAJOR RISK FACTORS’

In a very recent study looking at data from 91 058 men and 245 186 women, diets high in fruit and cereal fibre [‘fiber’] were associated with reduced incidence of CHD, and an even larger reduction in death from CHD.  Each 10-g/day increment of total dietary fiber was associated with a 14% decrease in risk of all coronary events and a 27% decrease in risk of coronary death. Results were similar for men and women.  Some of this favourable result may have been due to better blood sugar control (see DIABETES above). “Dietary Fiber and Risk of Coronary Heart Disease. A Pooled Analysis of Cohort Studies”,Pereira, 2004; Arch Intern Med. 164:370-376.

Animal experiment showed high-fat, refined carbohydrate over a lifetime induced hypertension and ‘reactive oxygen’ stress (overload of the body’s antioxidants)              Roberts, 2000; Hypertension 36:423-429

The same researchers later showed that for overweight humans, rigorous low-fat, high fibre diet and exercise induced weight loss (in 3 weeks) and dramatically improved: blood pressure, lipids / cholesterol, oxidative stress, insulin.  Carbohydrates were primarily from high-fibre whole grains, fruit, vegetables. Only 10% of calories were from fat. Roberts, 2002; Circulation. 106:2530-2532

 ‘AVOID THE ‘SUGAR HIT’

• Easily dissolved sugar or starch (the standard measurement uses white bread)
• quickly ‘spikes’ blood sugar
• acutely lowers arterial performance / tone for more than 2 hours
• causes acute oxidation stress

Title, 2000; J Am Coll Cardiol  36:2185-2191

 ‘AVOID THE ‘FAT HIT’

A high fat meal

dramatically reduces arterial elasticity (tone / ‘compliance’) for more than 6 hours and increases lipids (cholesterol, triglycerides ) compared with a low fat meal.                      Nestel, 2001; Am Coll Cardiol 37:1929-1935.

A high fat meal

dramatically reduces blood flow capability in coronary artery for more than 7 hours and might contribute to ‘postprandial’ angina. Hozumi, 2002; Ann Intern Med; 136:7, 523-528. Similarly, the endothelium, the artery lining, is disturbed after a high fat meal.               Ferriera,2004; Circulation. 110: 3599-3603.

 SMOKING

Long term smokers typically have impaired linings to their arteries and are susceptible to artery constriction and coronary and cerebral artery disease. Smoking makes the blood platelets more likely to shear and contribute to a clot.                                           Rubenstein, Circulation.2004;109:78-83.  Smoking a single cigarette increases oxidative stress and reduces antioxidant (vitamin C) in the blood and gives rise to signs of artery dysfunction. Tsuchiya, 2002; Circulation. 106(20) Smoking cessation in England & Wales over the last 20 years reduced CHD deaths by 25% (50% of the 50% decrease in CHD deaths 1981 - 2000) Belgin, 2004; Circulation 109;1101-1107.

 MOOD & STRESS MANAGEMENT

REMEMBER CARDIAC REHABILITATION CAN ADDRESS EMOTIONAL DISTRESS

‘SOCIAL SUPPORT’

1.Dr Ornish long-term combined diet & exercise programme had social support as key. Intensive lifestyle change reduced coronary artery blockages more after 5 years than after 1 year. In contrast control group disease continued to increase.                             Ornish, 1998; JAMA. 280:2001-2007  The original ‘Ornish Lifestyle’ combined exercise, with stress management training, social & psychological support, and a mostly vegetarian diet (fat was 10% of calories). The mainly vegetarian diet was to seriously reduce intake of cholesterol and saturated fat.

2. Reducing Emotional Distress Improves Prognosis in Coronary Heart Disease 9-Year Mortality in a Clinical Trial of Rehabilitation  (Denollet,2001; Circulation. 104:2018.)  Department of Clinical Health Psychology, Tilburg University, The Netherlands and the Center for Cardiac Rehabilitation, University Hospital of Antwerp, Belgium. After 9 year follow up, rate of death was 17% (12/72) for control patients versus 4%(3/78) for rehabilitation patients.

Rehabilitation was effective in reducing mortality although numbers in the trials were relatively small.

Social environment influences the Progression of Atherosclerosis in the Watanabe Heritable Hyperlipidemic Rabbit. McCabe,2002;Circulation. 105:354-359

DEPRESSION is linked to coronary artery disease¹

First lines of defence are

• Moderate exercise
• Check omega 3 fat intake is high enough
• Try social support (friends, neighbours, group, healers)
• Try stress reduction such as ‘slow breathing’, ‘yoga’, SEE BELOW

MENTAL STRESS triggers artery constriction (myocardial ischemia) and in one study² halves, for about 45 minutes, healthy arteries’ ability to dilate. Other studies show how chronic stresses (for example care giving for a spouse with dementia) increase general inflammation. The pro-inflammatory marker IL6 is associated with cardiovascular disease, osteoporosis, arthritis, type 2 diabetes, certain cancers, Alzheimer’s disease, periodontal disease, and frailty and functional decline.³

¹⁾Reviewed in Rozanski, 1999; Circulation 99:2192-2217.   ²⁾ Spieker, 2002; Circulation, 105:2817-2820.  ³⁾ Kiecolt- Glaser, 2003; PNAS 100:15: 9090-9095

DEPRESSION AND EXHAUSTION help destabilise arterial plaque (‘blockages’) and MENTAL STRESS can help rupture the plaque. “The immune system plays a role in the progression of coronary artery diseases [and is affected by stress]”                                 Gidron, 2003; Brain Behav Immun. 17(4):233

 YOGA SLOW BEATHING

 around 6 breaths per minute

• increases blood oxygen saturation¹
• improves arterial baroreflex sensitivity²
• apparently protects patients with chronic heart failure and previous MI (heart attack)²
• improves tolerance of exercise^1,3
• is recommended for chronic heart failure²
• helps reduce angina pain and thereby the achievement of normal mobility³

¹⁾Bernardi, 1998; Lancet 351:1308-1311; ²⁾ Bernardi, 2002; Circulation. 105:143; ³⁾ see reference 9 in Lewin, 1999; Heart. 82:654-655

  SLOW BREATHING ACCOMPANIED BY POSITIVE MOOD TRAINING

• improves mood⁴
• increases DHEA hormone (deficient in CHD and other disease states) and balances stress hormone⁵
• improves aspects of the immune system⁶
• probably improves blood pressure⁷

⁴⁾McCraty, 1995; Am. J. Cardiology 76:(14):1089-1093.⁵⁾McCraty, 1998; Integ. Phys. Behavioral Sci. 33(2): 151-170.⁶⁾McCraty, 1996; Stress Medicine 12. (3):167-175.⁷⁾ Barrios-Choplin, 1997; Stress Medicine 13:3,193-201 All ^4-7 are available at http://www.heartmath.org/research/research-papers/index.html

‘slow breathing’ is being investigated as a tool to look at control of blood circulation and related patient risk assessment⁸

⁸⁾Halámek, 2003; Circulation. 108:292.

Remember that social environment influences the progression of atherosclerosis, in the Watanabe heritable hyperlipidemic rabbit.  McCabe,2002; Circulation. 105:354-359

 LIFESTYLE COMBINED WITH MEDICATION

Aggressive lifestyle modification (diet and exercise) coupled with statin therapy can slow or reduce calcium deposits in the coronary arteries of patients who are at high risk of CAD but who do not have symptoms. Dr.V Goh, American Heart Association's Second Asia Pacific Scientific Forum, Honolulu, June 2003

Remember that intensive lifestyle change reduced coronary artery blockages more after 5 years than after 1 year without medication, in the original Lifestyle Study            ‘Ornish’. 1998; JAMA. 280:2001-200

 MODERN STATINS AT HIGH DOSE USUALLY SERIOUSLY REDUCE ARTERY ATHEROMA^1&2 AND CAN BE COMBINED WITH LIFESTYLE RISK FACTOR MODIFICATION

1) Reversal of Atherosclerosis with Aggressive Lipid Lowering (REVERSAL): A Prospective, Randomized, Double-blind, Multi-center Study Comparing the Effects of Atorvastatin Versus Pravastatin on the Progression of Coronary Atherosclerotic Lesions as Measured by Intravascular Ultrasound. Steven Nissen, MD. Presented at American Heart Association's Scientific Sessions 2003 on Wednesday, November 12, 2003. Read an account at http://www.clevelandclinic.org/heartcenter/pub/news/archive/2004/reversal5_2print.htm and later publication at

http://jama.ama-assn.org/cgi/content/abstract/291/9/1071 and Nissen,2004; JAMA. 291:1071-1080.

2) Relation Between Progression and Regression of Atherosclerotic Left Main Coronary Artery Disease and Serum Cholesterol Levels as Assessed With Serial Long-term Follow-up >12 Months Intravascular Ultrasound. Birgelen C. Von, 2003; Circulation 108:2757 - 2762

 3) Early Statin Treatment in Patients With Acute Coronary Syndrome

Demonstration of the Beneficial Effect on Atherosclerotic Lesions by Serial Volumetric Intravascular Ultrasound Analysis During Half a Year After Coronary Event: The ESTABLISH Study. Shinya, 2004; Circulation. 110:1061-1068.

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