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Cardiovascular Disease in the Tropics
• There are the differences in the pattern of cardiovascular disease in a country;
• HIV may contribute to the fall of endomyocardial fibrosis and the rise of pericarditis; may lead to a rise of tuberculous and pyogenic pericarditis;
• local factors in pathogenesis.

Rheumatic Cardiac Disease
It cripples and disables children in the tropics, young adults – the pattern is changing.
In much of Africa rheumatic fever and rheumatic heart disease account for 12-30 % of cardiovascular morbidity.
Rheumatic fever has different clinical features and affects the heart more commonly both in the first attack and in recurrences.

Epidemiology:
Risk factors:the poor; the poorly housed;
• the overcrowded are affected;
Prevalence data show that there are more cases in those parts of the tropics where rainfall is sparse and there is a harsh dry season (easier acquisition of Streptococcus pyogenes in a hot dry climate)
Acute carditis is recognized much less frequently.
Rheumatic fever follows infection with Streptococcus pyogenes.
Arthralgia may occur instead of arthritis in the tropics.

Clinical Features
The children may have:
• a low grade fever;
• a tachycardia;
• bacterial endocarditis;
• a cardiac murmur – in systole or in diastole, at the apex of the heart.
Rheumatic heart disease:
• mitral incompetence;
• mitral stenosis or mixed stenosis and incompetence;
• combined mitral and aortic lesions;
• the aortic valve alone;
The distinction between a streptococcal and a viral infection may be difficult.

Prevention:
• Improve housing, food and health care
• Detect and treat symptomatic Streptococcus pyogenes sore throat with:
 benzathine penicillin 1.2 mega units;
 penicillin V for 10 days;
 benzyl penicillin.
• Secondary prophylaxis of streptococcal infection:
 give benzathine penicillin every three weeks
 the dose of benzathine penicillin, every 3 weeks, is 600000 units for those of 30 kg or less, and 1.2 mega units for others
 sulphadiazine 0.5 or 1g.daily is an alternative.
• Vaccination of those at risk
• Maintain penicillin prophylaxis to prevent recurrences and infective endocarditis
• Give standard treatment for valvular disease

Dilated Cardiomyopathy
Men are affected more than women predominantly in the age group 40 – 49 years. Anaemia may be associated with cardiac failure, it does not appear to be a causal factor in dilated cardiomyopathy in the tropics.
Causes of cardiomyopathy:
• Alcohol;
• nutrition and micronutrients;
• previous viral myocarditis;
• genetic factors;

Clinical features
Most patients have had some of the typical symptoms of systemic oedema for up to two years before.
Clinical Signs:
• a large liver;
• ascites;
• the heart is large;
• panystolic murmurs with a third heart sound;
• intracavitary left ventricular thrombus;
• praecordial pulsation varies;
• atrioventricular valvular incompetence;
• jugular pulse.

Diagnosis:
If no evidence of valvular disease the diagnosis is not difficult.
In case of raised arterial pressure retinal arterial changes are possible.
The distinction from hypertensive cardiac failure may be difficult.
In case of mitral incompetence, rheumatic heart disease and even endomyocardial fibrosis may have to be considered.

Management and Prognosis:
• Diuretics with digoxin, when an atrial arrhythmia
• Vasodilators
The prognosis depends on the function of the left ventricle.
Those who do worst have a high left ventricular and diastolic pressure, with a reduced ejection fraction in systolic and diastolic volume.

Peripartum Cardiac Failure
The clinical syndrome dominates the signs, management and cause, and the cause is often not obvious.
The essential issue of PPCF is cardiac failure, without a definable cause developing in a woman who is or was recently pregnant.
May conceal a number of conditions.
The syndrome is primarily one of a dilated cardiomyopathy.
• The largest reported series have been in West Africans;
• PPCF is more common in multiparous women;
• PPCF is twofold in a twin pregnancy;
• No data which establish PPCF patients as having a particular genetic; predisposition, notably a distinctive human leukocyte antigen;
• Endomyocardial biopsy has given evidence in over 50% of cases of myocarditis.

Symptoms:
• Swelling of the whole body;
• Jugular venous pressure;
• Altering arterial pulsus;
• Enlarged or hyper dynamic left ventricle;
• Systemic and pulmonary emboli are seen when the heart is very large;
Investigations:
The chest radiograph shows a dilated heart, pulmonary venous congestion and oedema;
No typical pattern;
Treatment:
• Diuretics;
• Immunosuppressant drugs;
• Continuous antenatal and postnatal care;
• Routine treatment for cardiac failure.

Hypertension and Hypertensive Heart Disease
Most people in the tropics with high blood pressure do not know that they are hypertensive.
No supplies of the ideal combination of antihypertension drugs.
Migration apparently affects the blood pressure in women less than men.
Those of black African origin are most susceptible and, as discussed below, they are vulnerable to stroke; low rennin hypertension is also more common.
Stroke is a common problem in hospital practice in the tropics and it is closely correlated with hypertension.
Hypertensive cardiac failure has already been discussed in relation to dilated cardiomyopathy.
Malignant hypertension is well recognised and renal failure with severe hypertension is also often seen.
Retinopathy occurs in hypertension.
Management:
• Drugs with an angiotensin-converting enzyme;
• A beta blocker;
• A calcium channel blocker;
• Diuretics.

Endomyocardial Fibrosis
In the hot and humid tropics the disease is seen much more commonly.
In the case of necropsy the left ventricle with a curious thickening of the endocardium
-Chiefly at the apex.
Endocardial thickening of the ventricle leads to physiological effects: cardiac constriction or restriction and atrioventricular valvular incompetence leading to regurgitation.
In the left ventricle dense fibrous tissue at the apex spreads around the cavity of the ventricle or may first appear around the papillary muscle of the posterior cusp of the mitral valve.
• Advancing fibrosis of layered mural thrombi;
• The tricuspid valve loses its function;
• The right atrium can become aneurismal;
• Chronic pericardial effusion can be associated with right ventricular EMF;

• A pleural effusion is more common with left or biventricular disease;
• In acute disease, however, the pericardium, myocardium and endocardium are affected;
• There is active inflammation with lymphocytes, eosinophils which may be degranulated.

Pathogenesis:
Changes are similar to those found in the heart in patients with hypereosinophilic syndromes.
Linked filariasis with EMF, and particularly Loa Loa, or any other helminth which provokes an eosinophilia.
Helminthic or any other infection leads to hypereosinophilia and liberation of eosinophilic cationic protein and major basic proteins.
EMF is apparently more prevalent with the tropical splenomegaly syndrome.

Clinical Features:
• The anatomical distortion of whichever ventricle is dominantly affected
• Symptoms of pulmonary venous congestion
• Pulmonary hypertension
• Slight exophthalmos, central cyanosis
• No peripheral oedema and massive ascites
• The jugular pressure is very high
• Jugular vein is palpable; the stroke volume is small
• The arterial pulse has a small pulse pressure
• Atrial fibrillation is common
• A large pericardial effusion

Investigations:
• Findings on the chest radiograph;
• A massive cardiac shadow;
• Echocardiography is used;
• There is no specific diagnostic test.

Diagnosis and Management
• The initial illness may resemble acute myocarditis or acute rheumatic fever
• Established mitral incompetence-EMF
• Signs of cardiac construction(constructive pericarditis is more common than left ventricular EMF)
• Digoxin can be used to control ventricular rate
• If patients present with a short history and an unstable state they should be managed as for any acute myocarditis

Pericardial Disease
In the tropics there are two important forms of pericarditis, both secondary to a major primary disease:
1. Acute pyogenic pericarditis
2. Tuberculous pericarditis
Local and systemic signs are dominant and pericarditis may not be recognized until it causes circulatory effects.

Clinical features:
• Symptoms and signs of cardiac tamponade develop;
• The heart is compressed;
• The signs depend on obstruction to venous inflow and a subsequent fall in stroke output;
• There may be evidence of pericarditis – a pericardial rub or signs of fluid
• An impalpable cardiac impulse and very quiet heart sounds
• Evidence of intense peripheral vasoconstriction: empty veins and rapid arterial pulse, pulsus paradoxus.
• Signs of effusion are dominant.

Management:
• Echocardiography
• A chest radiography may reveal a large cardiac shadow
• Pericardial fluid confirms the diagnosis
• Aspiration by the epigastric approach ( use a 50 ml, or 20 ml syringe)
• The antibiotic chosen depends on the organism identified or suspected as a primary pathogen.
• In pericardial effusion with cardiac tamponade the fluid must be aspirated immediately and completely.

Tuberculous Pericarditis
Mycobacterium tuberculosis is thought to reach the pericardium from adjacent infection in lymph nodes or possibly pleura.

Clinical Picture
The clinical picture depends on the stage of the disease.
• Jugular venous pressure is very high;
• Those who have HIV/AIDS often show evidence of early pericardial infection;
• Pericardial effusion with underlying pericardial fibrosis (a small arterial pulse pressure, sometimes with pulsus paradoxus, the heart may be impalpable, a third heart sound is audible);
• In patients with HIV / AIDS signs of pericarditis must be assumed to be caused by tuberculosis;
• The fluid has high protein content around 40 g/l and in about 80 % of cases it is bloodstained.

Treatment:
• Give antituberculosis drugs with corticosteroids;
• Give prednisolone 2 mg /kg.

Other Infections
Signs of pericarditis may be detected in patients with meningococcal disease who have bacteraemia and antigenaemia.
Immune complexes are formed and deposited on the pericardium.
Parasites:
Protozoan pericarditis is caused by trophozoites of entamoeba histolytica (the prognosis in this complication is bad)
• Metronidazole and chloroquine orally;
• Metronidazole injected into the pericardial sac.

Arterial Disease
Tropical aortitis (idiopathic) is more common in the tropics:
• Pathological /anatomical damage to the aorta and its large branches;
• Regional ischemia in a tissue is the most common;
• Stenosed segments of aorta with an irregular lumen;
• There is a systemic inflammatory phase in some patients;
• An associated glomerulonephritis in some patients may be suggestive evidence.
Clinical Features:
• Symptoms associated with hypertension;
• Symptoms of transient cerebral ischemia;
• Renal artery stenosis may be audible in up to 50 % of cases;
An aortogram is definite. Selective renal angiography can be used if the abdominal aorta is obviously abnormal.
Management:
• In most patients in the tropics no treatment is possible;
• Angioplasty or an arterial bypass may be used;
• The arterial damage is widespread and treatment is unlikely to help.

Coronary Arterial Disease
• Cardiac pain;
• Severe anaemia from untreated heavy hookworm infection can lead to qualitative effect in coronary arterial flow;
• The coronary arteries or their lumens may be occluded or stenosed;
• Mural thrombi form and may partially fill the aneurysm and lead to systemic emboli.

Vocabulary

To cripple [`krǐpl] Шкодити,ослаблювати
Sparse [`spα:s] Рідкий .розсіяний
Acquisition [ækwǐ`zǐ∫n] Набування
Valve [`vælv] Клапан(серця)
Multiparous women [məltǐ`pærəυəs`wi:mǐn] Жінка,яка народила кількох дітей
Twofold [`tu:fəυld] Подвійний, вдвічі
Posterior cusp [pəυs`tǐərǐə`kǎsp] Задній кінчик
Tricuspid valve [tra ǐ`kǎspǐd`vælv] Потрійний клапан
Aneurysmal [ænјυ`rǐzməl] Розширюючий артeрії
Pericardial sac [pǐrǐ`kα:dǐəl`sæk] Перикардіальний мішечок
Be occluded [bǐ ə`klu:dǐd] Бути прихованим
Delated [dǐ`leǐtǐd] Розширений
Ascites [`æsa ǐts] Асцит
Jugular [`dзυgјυlə] Шийний
Retinal [`retǐnl] Приналежний до сітківки ока
Vasodilators [vəsəυdǐ`leǐtəz] Судинорозширювачі
Regurgitation [rǐgədзǐ`teǐ∫n] Зворотній потік крові
Mural thrombi [`mјu:rl`θrombǐ] Стінкові тромби
Atrium [`ætrǐəm] Передсердя
Tamponade [`tæmpə`neǐd] Застосування тампонів
Lumen [`lu:mǐn] Люмен, просвіт потоку(вени)
Be stenosed [bǐ`stenəυzd] Бути звуженим

Questions
1. What is so important in case of dilated cardiomyopathy?
2. What are the clinical features and epidemiology of tropical rheumatic cardial disease?
3. How can we define the clinical features of peripartum cardiac failure?
4. Are there any peculiarities of hypertensive heart disease in the tropics?
5. What is endomyocardial fibrosis? What are the clinical features and pathogenesis?
6. How does the tuberculous pericarditis manifest itself in the HIV-infected?
7. What are the clinical features of pericardial and arterial diseases?

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