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SAMIKSHA HEART AND DIABETIC CARE ''CONNECTIVE TISSUE DISORDERS'' ''Marfan Syndrome'' Marfan syndrome is a systemic connective tissue disorder with a frequency of 2 to 3 in 10, 000. The disorder is characterized by manifestations involving the cardiovascular, skeletal, and ocular systems. Current diagnostic criteria are based on involvement of above organ systems and family history. Cardiovascular manifestations include mitral valve prolapse, progressive aortic root enlargement, and ascending aortic aneurisms, possibly leading to aortic regurgitation, dissection, or rupture. Some characteristic skeletal manifestations of this syndrome include disproportional increase of linear bone growth resulting in malformations of the digits (arachnodactyly), craniofacial abnormalities, pectus excavatum/carinatum, and scoliosis. A common ocular involvement is severe myopia and lens dislocation in one or both eyes (ectopia lentis). Marfan syndrome is an autosomal dominant disorder caused by fibrillin-1 gene mutations encoding for the extracellular matrix protein fibrillin (Fbn-1). Fibrillin is an integral component of both elastic and nonelastic connective tissue. The mechanism of fibrillin mutation in Marfan syndrome remains unclear. However, animal models of Fbn-1 have demonstrated a role of TGF-beta signaling. In some patients with phenotypes similar to Marfan syndrome but without fibrillin- 1 gene mutations, TGF-beta receptor mutations have been identified, suggesting a significant role of TGF-beta pathway in the pathogenesis of Marfan syndrome features. Aortic root involvement remains the leading cause of death in patients with Marfan syndrome. Echocardiography is recommended to routinely screen and to follow aortic root dilation. In addition, all first-degree relatives of the family should have screening echocardiography. Patients should be advised against strenuous exercises. Medical therapy for Marfan syndrome includes beta-blockers to reduce myocardial contractility and pulse pressure. Animal models of Marfan syndrome have demonstrated a possible benefit of losartan in preventing progression of the disease by inhibiting the TGF-beta pathway, and this therapy is the subject of an active clinical trial. Elective aortic root replacement remains the therapy of choice once the aortic root becomes significantly enlarged. Marfan patients who become pregnant need to be counseled not only about the 50% chance of transmitting the disease but also the substantially increased risk of aortic rupture/dissection during and after pregnancy. Important components of Marfan syndrome counseling are consideration of contraception and pregnancy management. Loeys-Dietz Syndrome Recently, an aortic aneurysm syndrome has been identified with TGF-beta receptor mutations. Loeys-Dietz syndrome is an autosomal dominant condition with a characteristic triad of arterial tortuosity/aneurysm, hypertelorism, and bifid uvula or cleft palate. There is significant overlap with Marfan syndrome, and the management is similar in terms of cardiovascular manifestation. Early, elective, surgical intervention should be considered in patients with significant aneurysmal dilation of the aorta. Some clinicians have argued for much earlier surgical intervention for the dilated aorta in this condition, compared with Marfan syndrome, since there appears to be a much greater risk of rupture and dissection at earlier ages and smaller aortic sizes. Pregnancy counseling is also an integral part of therapy. Ehlers-Danlos Syndrome Ehlers-Danlos syndrome is a group of disorders that affect connective tissue development due to defects in collagen and connective tissue biosynthesis. Prevalence of the disease is about 1 in 400, 000 people in the United States. Cardiac manifestations include spontaneous rupture of medium to large sized arteries including the aorta. Frequently, extracardiac presentations include hyperextensible skin and hypermobile joints. To date, 11 types of the disorder have been recognized, but collagen defects have been described in only 6 types. Although all types of Ehlers-Danlos syndrome affect the joints and the skin, clinical features vary by type. Different features characterize each type of the syndrome. Type IV carries the poorest prognosis, especially due to spontaneous ruptures of arteries and organs. Extreme caution needs to be taken if surgical intervention is needed due to weakened connective tissue structures. Many genes, including ADAMTS2, COL1A1, COL1A2, COL3A1, COL5A1, COL5A2, PLOD1, and TNXB, have been implicated in the pathogenesis of Ehlers- Danlos syndrome, but the predominant cardiovascular concern exists in the Type IV vascular form of Ehlers-Danlos associated with mutations in the COL3A1 gene and aortic dilation/aneurysms. Other less commonly associated anomalies include ventricular septal defect, patent ductus arteriosus, bicuspid pulmonic valve, and Ebstein’s anomaly. Bicuspid aortic valve has been shown to demonstrate familial clustering. However, identifying culprit genes have been difficult due to variable penetrance and the common nature of the disorder.
THE BEST CARDIOLOGISTS IN YELAHANKA Aortic regurgitation The incompetent aortic valve allows regurgitation of blood from the aorta to the left ventricle during diastole for as long as the aortic diastolic pressure exceeds the left ventricular diastolic pressure. Symptoms: Occur in the late stages of disease and include exertional dyspnoea, fatigue, palpitations (hyperdynamic circulation) and exertional angina. General signs: Marfan’s syndrome may be obvious. The pulse and blood pressure: The pulse is characteristically collapsing; there may be a wide pulse pressure. The neck: Prominent carotid pulsations (Corrigan’s sign). Palpation: The apex beat is characteristically displaced and hyperkinetic. A diastolic thrill may be felt at the left sternal edge when the patient sits up and breathes out. Auscultation): A2 (the aortic component of the second heart sound) may be soft; a decrescendo high-pitched diastolic murmur beginning immediately after the second heart sound and extending for a variable time into diastole—it is loudest at the third and fourth left intercostal spaces; a systolic ejection murmur is usually present (due to associated aortic stenosis or to torrential flow across a normal diameter aortic valve). Signs indicating severe chronic aortic regurgitation: Collapsing pulse; wide pulse pressure; long decrescendo diastolic murmur; left ventricular S3 (third heart sound); soft A2; signs of left ventricular failure. Causes of chronic aortic regurgitation: (i) Rheumatic (rarely the only murmur in this case), congenital; (ii) aortic root dilatation—Marfan’s syndrome, dissecting aneurysm. 8• THE PATIENT WITH A MURMUR 305 a b Valve cusps often thickened and calcified Left ventricle may be hypertrophied Ascending aorta may be dilated Systole Diastole S1 A2 P2 S1 Ejection click (Suggests congenital AS) Normal Mild S1 S1 Moderate S1 P2 A2 S1 Severe Reversed S2 Single (S2)
THE BEST CARDIOLOGISTS NEAR HSR LAYOUT Coronary angiography (cardiac catheterisation) This procedure enables the cardiologist to visualise the coronary arteries . It is the standard against which other less-invasive investigations are assessed. Selective catheterisation of the right and left coronary ostia is performed. Contrast is then injected into the vessels and digital tape or disc storage of the images obtained. In most hospitals the patient is admitted on the morning of the test and allowed to go home that afternoon. The procedure is most often performed through the femoral artery (Judkins technique) . This artery can be punctured through the skin under local anaesthetic. A fine softtipped guide wire is then advanced into the artery and the needle withdrawn (Seldinger method). A short guiding sheath can then be placed over the wire and long cardiac catheters advanced through this sheath along a long guide wire into the femoral artery and up via the aorta to the aortic arch. The catheter and wire are advanced under X-ray control. Usually one catheter with a curved tip (pig-tail catheter; is advanced across the aortic valve into the left ventricle where left ventricular pressures are measured via a pressure transducer connected to the other end of the catheter. Measurement of the left ventricular end-diastolic pressure gives an indication of left ventricular function. Raised end-diastolic pressure (over 15 mmHg) suggests left ventricular dysfunction . The catheter is then connected to a pressure injector. This enables injection of a large volume of contrast over a few seconds; for example, 35 mL at 15 mL/second. X-ray recording during injection produces a left ventriculogram , Here left ventricular contraction can be assessed and the ejection fraction (percentage of end-diastolic volume ejected with each systole) estimated. The normal is 60% or more. The figure obtained by this method tends to be higher than that produced by the nuclear imaging method—gated blood pool scanning. The guide wire is reintroduced and the catheter withdrawn to be replaced by one shaped to fit into the right or left coronary orifice...
CADIOLOGISTS IN VIDHYARANYAPURA Coronary angiography (cardiac catheterisation) This procedure enables the cardiologist to visualise the coronary arteries It is the standard against which other less-invasive investigations are assessed. Selective catheterisation of the right and left coronary ostia is performed. Contrast is then injected into the vessels and digital tape or disc storage of the images obtained. In most hospitals the patient is admitted on the morning of the test and allowed to go home that afternoon. The procedure is most often performed through the femoral artery (Judkins technique) This artery can be punctured through the skin under local anaesthetic. A fine softtipped guide wire is then advanced into the artery and the needle withdrawn (Seldinger method). A short guiding sheath can then be placed over the wire and long cardiac catheters advanced through this sheath along a long guide wire into the femoral artery and up via the aorta to the aortic arch. The catheter and wire are advanced under X-ray control. Usually one catheter with a curved tip (pig-tail catheter; is advanced across the aortic valve into the left ventricle where left ventricular pressures are measured via a pressure transducer connected to the other end of the catheter. Measurement of the left ventricular end-diastolic pressure gives an indication of left ventricular function. Raised end-diastolic pressure (over 15 mmHg) suggests left ventricular dysfunction The catheter is then connected to a pressure injector. This enables injection of a large volume of contrast over a few seconds; for example, 35 mL at 15 mL/second. X-ray recording during injection produces a left ventriculogram . Here left ventricular contraction can be assessed and the ejection fraction (percentage of end-diastolic volume ejected with each systole) estimated. The normal is 60% or more. The figure obtained by this method tends to be higher than that produced by the nuclear imaging method—gated blood pool scanning. The guide wire is reintroduced and the catheter withdrawn to be replaced by one shaped to fit into the right or left coronary orifice. Hand injections of 5–10 mL of contrast are then made. Modern equipment enables numerous views of the coronaries to be obtained in both right and 4• THE PATIENT WITH CHEST PAIN 129 left oblique and caudal and cranial angulated views. The left system (left main, left anterior descending and circumflex arteries) is more complicated than the right, and more views are obtained ) It is also possible to catheterise the heart by direct puncture of the radial artery at the wrist, using a long sheath and a technique similar to the Judkins. Problems may be encountered advancing the catheters around the shoulder or if spasm of the radial or brachial artery occurs.
CARDIOLOGISTS IN HEBBALA Risk stratification using myocardial perfusion scans A normal perfusion scan is associated with a good prognosis. The annual rate of myocardial infarction of cardiac death is < 1%, at least for some years. Stress echocardiography Ischaemic areas of myocardium are known to have reduced contraction compared with normal areas. This can be demonstrated by high-quality echocardiograms. A number of standard views of the heart are obtained and the wall is divided into regions that are assessed for reduced motion. The echo equipment must be designed to store rest images and to present them next to stress images on a split screen so that direct comparison can be made. The stress can be provided by exercise or dobutamine infusion. Exercise echocardiography is difficult to perform because of movement problems and there is quite high inter-reporter variability, but both techniques can approach the accuracy of sestamibi testing in experienced hands. It is not possible to obtain images of adequate quality in all patients. Coronary angiography (cardiac catheterisation) This procedure enables the cardiologist to visualise the coronary arteries It is the standard against which other less-invasive investigations are assessed. Selective catheterisation of the right and left coronary ostia is performed. Contrast is then injected into the vessels and digital tape or disc storage of the images obtained. In most hospitals the patient is admitted on the morning of the test and allowed to go home that afternoon. The procedure is most often performed through the femoral artery (Judkins technique) . This artery can be punctured through the skin under local anaesthetic. A fine softtipped guide wire is then advanced into the artery and the needle withdrawn (Seldinger method). A short guiding sheath can then be placed over the wire and long cardiac catheters advanced through this sheath along a long guide wire into the femoral artery and up via the aorta to the aortic arch. The catheter and wire are advanced under X-ray control. Usually one catheter with a curved tip (pig-tail catheter;is advanced across the aortic valve into the left ventricle where left ventricular pressures are measured via a pressure transducer connected to the other end of the catheter. Measurement of the left ventricular end-diastolic pressure gives an indication of left ventricular function. Raised end-diastolic pressure (over 15 mmHg) suggests left ventricular dysfunction . The catheter is then connected to a pressure injector. This enables injection of a large volume of contrast over a few seconds; for example, 35 mL at 15 mL/second. X-ray recording during injection produces a left ventriculogram Here left ventricular contraction can be assessed and the ejection fraction (percentage of end-diastolic volume ejected with each systole) estimated. The normal is 60% or more. The figure obtained by this method tends to be higher than that produced by the nuclear imaging method—gated blood pool scanning. The guide wire is reintroduced and the catheter withdrawn to be replaced by one shaped to
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