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THE BEST CARDIOLOGIST IN HEBBALA Hypertension as a risk factor Hypertension is a risk factor for coronary disease, but even more so for cerebrovascular disease and left ventricular failure.1 Control of blood pressure reduces this risk. Large randomised trials have shown that every 10–14 mmHg reduction in systolic and 5 mmHg reduction in diastolic blood pressure confers a 29% reduction in CHD risk and a 40% reduction in stroke risk. The risk of a coronary event in a man with blood pressure greater than 160/95 is five times the risk in a man with blood pressure of 140/90 or less. Hypertension can be diagnosed only by blood pressure measurements. There is little evidence that high blood pressure causes symptoms, except for malignant hypertension with cerebral oedema. The symptoms often ascribed to hypertension—epistaxis, dizziness, headache and fainting—are no more common in hypertensives than in normotensives. Anxiety (often about the blood pressure) and hyperventilation may explain some of these symptoms.2 The trials providing the above figures have been carried out using diuretics or beta-­blockers in the treatment of hypertension. Because these drugs may adversely affect lipid profiles and therefore coronary risk, it has been suggested that newer agents may produce a greater reduction in the risk of CHD events. However, this has not been proven. There is evidence from metaanalyses of blood pressure lowering trials that beta-blockers are less protective against stroke than other agents. They are more effective than placebo in providing protection against stroke. The reduction in blood pressure that is achieved is still more important than the choice of drug. The trials have shown that blood pressure reduction in the elderly, including those over the age of 80, is associated with reduced cardiovascular morbidity but not all-cause (overall) mortality. Treatment of isolated systolic hypertension, common in the elderly, has also shown benefit in terms of the reduced risk of stroke, cardiac failure and coronary disease.3 As in the case of other risk factors, the greatest absolute benefit in the treatment of hyper-­ tension is gained in those patients with existing heart disease, diabetes or multiple risk factors. Blood pressure is an important component of the total risk score . The effects of hypertension Cardiovascular Sustained hypertension results in increased left ventricular wall thickness (left ventricular hypertro-­ phy, LVH) and may ultimately lead to left ventricular dilatation and cardiac failure. LVH results in higher oxygen demands by the ventricle, making angina more likely. The mechanism by which hypertension is thought to increase CHD risk is mechanical damage to the endothelium, leading to increased permeability and therefore increased atherogenesis. Elevated blood pressure interacts with other hereditary and acquired risk factors, all of which are associated with endothelial dysfunction; some are probably implicated in the genesis of hypertension in the first place.4 Neurological Hypertension
This ordinarily consists of monitoring of  is suspected. heart rate and rhythm,  repeated measurement of systemic arterial pressure by cuff,  obtaining chest radiographs to detect heart failure,  repeated auscultation of the lung fields for pulmonary congestion,  measurement of urine flow,  examination of the skin and mucous membranes for evidence of the adequacy of perfusion, and
THE BEST CARDIOLOGISTS IN YELAHANKA nvestigations of possible or probable stable angina Electrocardiography A standard 12-lead ECG should be obtained in all patients. This is likely to be normal in almost half of patients with subsequently proven coronary artery disease. Nevertheless, an abnormal trace lends weight to the symptoms and favours further investigation. Chest X-ray Routine radiology is not essential but may reveal important co-morbidities. It should always be performed in those with clinical evidence of hypertension, pericarditis (p. 174), heart failure or valvular disease, if only as a baseline. It is similarly indicated for patients with suspected or known pulmonary or systemic disease such as rheumatoid arthritis, COPD or alcoholism. Routine blood tests All patients with suspected angina should have the following routine investigations at presentation (NHF grade A recommendation): n fasting lipids, including total cholesterol, LDLs, HDLs and triglycerides—risk factors n fasting blood sugar—risk factor n full blood count—anaemia exacerbates angina n serum creatinine—impaired renal function is a risk factor and can be worsened by some cardiac investigations. If indicated clinically, thyroid function
POPULAR CARDIOLOGISTS IN H S R LAYOUT Ventricular tachycardia Ventricular tachycardia is defined as three or more ventricular ectopic beats at a rate over 100/minute. It is said to be sustained if it lasts more than 30 seconds. Most broad-complex tachycardias are ventricular (rather than supraventricular with aberrant conduction). The diagnosis of VT is greatly strengthened if there is a history of myocardial infarction or cardiac failure but, oddly enough, the patient’s haemodynamics are of no help. A number of criteria have evolved over the years to help ascertain the diagnosis of VT over aberrancy. These include: evidence of AV dissociation—P waves can be seen unrelated to the QRS complexes (they are usually visible only at relatively slow VT rates) the presence of supraventricular capture or fusion beats visible retrograde conduction with 2:1 block (P waves visible following every second complex) the presence of monophasic R, qR or QR patterns in V1, provided a septal infarction has not modified a RBBB a taller left rabbit ear in RR' or qRR' complexes in V1 n QS complexes in V1 with a slow S descent and sharp upstroke—the opposite of LBBB—or a broad small primary R wave in rS morphology (the Rosenbaum pattern) RAD in the frontal plane with LBBB-like QRS complexes
THE BEST HEART SPECIALISTS IN BANGALORE Angioplasty Balloon dilatation of coronary artery stenoses was first performed in the late 1970s by Andreas Grunzig. The technique has undergone many refinements and is now widely used for the treatment of angina not responding to medical treatment. Angioplasty has not been shown to improve the prognosis of patients with stable angina. Coronary artery bypass grafting (CABG) has similarly not been shown to prolong life for most stable angina patients. However, both treatments are very successful in relieving the symptoms of angina. The COURAGE Trial compared optimal medical treatment of angina with angioplasty but excluded patients with symptoms refractory to medical treatment.1 Not surprisingly, this group of stable mild angina patients had a similar outcome with angioplasty and medical treatment. The trial suggests that compared with optimal medical treatment, angioplasty is a safe and slightly more effective treatment for stable angina. Patients can make an informed choice between these two treatments. The majority of patients treated with angioplasty in Australia have acute coronary syndromes and here there is good evidence of prognostic benefit with angioplasty compared with medical treatment. In many centres one-, two- and complicated three-vessel disease are managed this way. It has been shown to be as effective as coronary surgery for these patients but at the price of a higher rate of re-intervention. This is because the greatest limitation of angioplasty is the rate of restenosis in vessels that have been dilated. Restenosis
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