Chagas' Disease
Chagas' Disease is an infection caused by the parasite, Trypanosoma Cruzi. It is spread by the bite and faeces of certain cockroach-like insects ("Vinchuca" bugs) found mainly in the rural areas of Central and Southern America. In the acute illness patients experience mild symptoms of fever, aches and swelling of the eyelids. Although many patients never develop any future symptoms, some go on to develop serious complications such as enlarged esophagus, enlarged colon or heart disease.
In the southern cone of Latin America it is estimated that 18 million people currently carry the parasite and 20-50% of these have or will develop some form of heart disease. The risk of parasite infection varies widely and is greatest in rural areas where humans live in close proximity to farm animals; therefore this is a prototypical disease of the poor - often the poorest of the rural poor. Economic growth in countries such as Brazil and Argentina has largely eliminated new cases of Chagas' disease but ongoing poverty and social dislocation in countries such as Bolivia are associated with an ongoing need for cardiac care of a growing number of adults.
Chagas' heart disease accounts for most of the mortality associated with chronic phase of Chagas' Disease. About 55-65% of deaths are due to sudden cardiac death, 25-30% are due to heart failure and 10-15% are due to stroke. During the chronic phase of Chagas' Disease patients are at risk for extremely slow heart rates caused by complete heart block as well as fast heart rates due to ventricular tachycardia. Permanent pacemaker and cardiac defibrillator implantations are the preferred treatment for patients suffering from this condition, sometimes supplemented by radiofrequency catheter ablation for atrial flutters and ventricular tachycardia. However, most patients in rural South America are not able to afford, and have no access to, these therapies.
Image imported from CDC.gov
Rheumatic Heart Disease
Rheumatic heart disease is a condition in which damage to the heart valves is caused by rheumatic fever, an illness that typically occurs in childhood. The disease generally begins with strep throat caused by Streptococcal bacteria and if untreated can eventually cause rheumatic fever.
In developing areas of the world, acute rheumatic fever and rheumatic heart disease are estimated to affect nearly 20 million people and are the leading causes of cardiovascular death during the first 5 decades of life. Patients with rheumatic heart disease suffer from thickening of the heart valves leading to obstruction in blood flow as well as valvular regurgitation.
The key to management of rheumatic heart disease is prevention with early treatment of strep throat with antibiotics. However in developing countries and poverty-stricken areas most children with strep throat do not have access to physicians and antibiotics. Once patients develop rheumatic heart disease, management focus is on monitoring progression of valvular disease and prevention of stroke. Patients with rheumatic valvular heart disease often require special procedures with catheters to open up obstruction - or valve surgery.
Mitral Balloon Valvuloplasty - X ray image showing a balloon across the mitral valve