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PAPULAR CARDIOLOGISTS IN HEBBALA ECG interpretation: points to remember 1 ECG reports should be short and based on clinical information where possible. 2 Check that the patient’s name is on the ECG and that the paper speed and calibration markers are correct. 3 Measure or estimate the heart rate—3 large squares = 100/minute. 4 Establish the rhythm. Look for P waves (best seen in L2). Are the P waves followed by QRS complexes? Look for anomalously conducted or ectopic beats. 5 Measure the intervals: PR, QRS duration and QT interval (for the latter, consult tables, but normal is less than 50% of the RR interval). 6 If the QRS complex is wide (> 3 small squares) consider the possibilities: LBBB, RBBB, WPW or ventricular rhythm or beats. If the pattern is of LBBB, there is no need in most cases to attempt further interpretation. 7 Estimate the QRS axis. In LAD, L1 and aVF diverge and L2 is predominantly negative. In RAD, L1 and aVF converge, while L2 matters little. Indeterminate axis is diagnosed when all six frontal leads are (more or less) equiphasic. 8 Check whether the criteria for LAHB or LAFB have been met. 9 Look for pathological Q waves. In general these are longer than 0.04 seconds and are more than 25% of the size of the following R wave.
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
HEART SPEACIALIST IN BANGALORE HYPERTENTION By definition, sinus tachycardia is a heart rate ≥ 100/minute and sinus bradycardia is a heart rate ≤ 50/minute.3 To calculate the heart rate from the ECG, the R-R interval in mm can be divided into 1500. For example, an R-R interval of 20 mm gives a rate of 75/minute and an R-R interval of 15 mm gives a rate of 100. Similarly, large 5 mm squares can be divided into 300; thus three squares give a rate of 100/minute. In regular rhythms, any two congruous points of the P-QRS-T sequence can be used to estimate the rate. An ECG ruler has a scale that enables rapid rate measurement and calculation of other intervals. With practice, the rate can be estimated at a glance.
CARDIOLOGIST IN YELAHANKA SECOND DEGREE AV BLICK There are two basic types of second-degree AV block: AV nodal Möbitz type I (Wenckebach) heart block, and the more distal and more sinister Möbitz type II heart block. Möbitz type I heart block is much more common. In Möbitz type I block the PR interval lengthens progressively with each cardiac cycle, until an atrial wave is not conducted. There is recovery of conduction and the next a wave is conducted with a shorter interval and the cycle begins again. The QRS complex is narrow (Fig 3.10) (unless associated with pre-existing BBB). The increment is largest between the first and second conducted P wave, and the PR interval continues to increase by less and less until a P wave is dropped. Möbitz type II heart block is almost always associated with a BBB (Fig 3.11), since its origin is intraventricular (below the AV node), and it tends to lapse suddenly into extreme bradycardia or asystole. It tends to be over-diagnosed, especially in the setting of 2:1 AV block (Fig 3.12). There is no lengthening of the PR interval before an atrial wave is not conducted. At times, atropine or exercise can demonstrate the site of the block, by increasing the block from 2:1 to a higher grade when the underlying mechanism is Möbitz II. Conversely, Wenckebach conduction may improve to 3:2 or better. For a distinction to be made between Möbitz type I and Möbitz type II, at least two consecutively conducted P waves have to be evaluated. This is impossible in 2:1 conduction (block) and can only be reported as 2:1 AV block (Fig 3.12). Yet this is very commonly reported as
THE BEST CARDIOLOGISTS IN YELAHANKA A systematic description of ECGs The following eight short steps will enable most ECGs to be described correctly: 1 Check the paper speed and calibration markers. 2 Measure or estimate the heart rate. 3 Estimate the rhythm. 4 Look for P waves. 5 Measure the PR interval. 6 Examine the QRS complex. 7 Check the ST segment. 8 Measure the T wave. ECG interpretation should always be as restrained as practicable, taking into account the clinical context where known and comparison with previous tracings where possible. The possibility of Prinzmetal’s electrocardiographic heart disease must always be borne in mind—that is, do not assume that an abnormal ECG always means heart disease.2.
POPULAR CARDIOLOGISTS IN SAHAKARANAGAR Left ventricular hypertrophy Although the ECG is reasonably specific, it is not as sensitive as echocardiography in detecting LVH. The LVH voltage alone may be a normal finding in younger subjects, but in adults over 35 years it usually connotes true LVH, especially if corroboratory findings are present Unfortunately, LVH with ST/T changes may be impossible to separate from LVH voltage complicated by ST/T changes of different, especially ischaemic, origin . Right ventricular hypertrophy The main criteria fSAor detecting RVH are RAD over +110° and a dominant R wave in V1 (in the absence of its other causes and in the presence of normal-duration QRS) In congenital heart disease conduction defects often come to obscure the hypertrophy patterns.
THE BEST CARDIOLOGISTS IN YELAHANKA Second-degree AV block There are two basic types of second-degree AV block: AV nodal Möbitz type I heart block, and the more distal and more sinister Möbitz type II heart block. Möbitz type I heart block is much more common. In Möbitz type I block the PR interval lengthens progressively with each cardiac cycle, until an atrial wave is not conducted. There is recovery of conduction and the next a wave is conducted with a shorter interval and the cycle begins again. The QRS complex is narrow (unless associated with pre-existing BBB). The increment is largest between the first and second conducted P wave, and the PR interval continues to increase by less and less until a P wave is dropped. Möbitz type II heart block is almost always associated with a BBB , since its origin is intraventricular (below the AV node), and it tends to lapse suddenly into extreme bradycardia or asystole. It tends to be over-diagnosed, especially in the setting of 2:1 AV block . There is no lengthening of the PR interval before an atrial wave is not conducted. At times, atropine or exercise can demonstrate the site of the block, by increasing the block from 2:1 to a higher grade when the underlying mechanism is Möbitz II. Conversely, Wenckebach conduction may improve to 3:2 or better. For a distinction to be made between Möbitz type I and Möbitz type II, at least two consecutively conducted P waves have to be evaluated. This is impossible in 2:1 conduction (block) and can only be reported as 2:1 AV block (Fig 3.12). Yet this is very commonly reported as Möbitz type
CCARDIOLOGIST IN DODDABOMMASANDRA, BANGALORE ardiac drugs A detailed drug history is essential. Ask about anti-anginal and anti-failure drugs. It is important to attempt to ensure that the patient gets these drugs on the day of the operation. This applies most of all to beta-blockers. Withdrawal of beta-blockers used for angina can precipitate unstable angina or an infarct. There is also evidence that the use of beta-blockers in the peri-operative period reduces the risk of significant ischaemic events.36 This is probably not the case for nitrates and calcium antagonists. Aspirin used for any patient with ischaemic heart disease should be stopped for the shortest possible period before surgery (about three days) . Warfarin, when used for protection against embolic events for atrial fibrillation, can usually be stopped four or five days pre-op and begun again soon afterwards. A possible exception is a patient with atrial fibrillation and a recent embolic event or a left atrial thrombus seen on echo. These patients may need to change to heparin, as detailed below. A history of infective endocarditis, known valvular heart disease (even if mild) or the presence of a prosthetic cardiac valve may be an indication for antibiotic prophylaxis. Patients with a prosthetic heart valve who are taking warfarin need careful management. If the valve is in the aortic position and it is a modern disc valve, it may be safe to allow the INR to fall moderately (to 1.8 or so) by the day of surgery and then to resume warfarin as soon as the patient can swallow. If the surgeon requires the INR to have fallen to normal or the patient has a valve in the mitral position, then cessation of warfarin and use of heparin is necessary. Normally the patient omits a warfarin dose and then is admitted to hospital three or four days before surgery. Intravenous heparin is begun and the APPT adjusted to 2 or 2.5 times normal. The heparin is stopped some hours before surgery and begun as soon afterwards as the surgeon allows. It is now possible, however, to use low molecular weight heparin instead
HEART DOCTORS IN YELAHANKA NEWTOWN, BANGALORE Management of ACS (NSTEACS) Patients with this diagnosis represent a rather heterogeneous group. Some have had the recent onset of angina at the extremes of exercise, others have angina at rest associated with ECG changes. This variation has made attempts to study the effects of different treatment rather difficult. Although the majority of patients with myocardial infarction have a preceding period of unstable angina, only about 5% of all patients admitted to hospital with a diagnosis of an ACS go on to infarct during that admission. The in-hospital mortality for these patients is low. Mortality rates of less than 2% are usual. Nevertheless, there is a real short-term and longerterm risk of infarction, recurrent admission with unstable symptoms and death which is higher than that of patients with stable angina. The diagnosis should therefore lead to admission to a CCU. The cardiac enzymes are, by definition, not elevated in these patients but the newer, more sensitive tests for troponin T and troponin I may be abnormal and indicate a worse prognosis . In the CCU, bed rest, oxygen and ECG monitoring are routinely enforced and any mobile phones taken away (allegedly to protect the monitoring equipment). Recurrence of chest pain can be assessed quickly and ECGs performed to look for changes suggesting infarction. The cardiac biomarkers can be checked regularly. All patients should receive aspirin (300 mg) unless there is a contraindication. Patients with an intermediate or a higher risk should also be given clopidogrel (usually a 300–600 mg loading dose). The use of intravenous heparin has become standard treatment. A typical starting dose is 5000 units as a bolus followed by 24, 000 units over 24 hours. The activated partial thromboplastin time (APPT) should be measured after about six hours of treatment and the infusion rate of heparin adjusted to maintain this at about twice normal. Heparin is generally safe when used in this way. Bleeding problems may sometimes occur and the platelet count should be checked every few days so that heparin-induced thrombocytopenia (HITS), a rare but serious complication, can be detected early. Low molecular weight heparins are at least as effective as unfractionated heparin. These drugs have some advantages over heparin. Their dose response effect is more predictable and they cause less thrombocytopenia. They are effective given subcutaneously without APPT monitoring and are now cheaper than IV heparin when savings on APPT monitoring and the use of infusion sets are considered. A standard twice-daily dose is given according to the patient’s weight—1 mg/kg for enoxaparin (Clexane). The dose is reduced by half for those with moderate or severe renal impairment and for those over the age of 75. Additional treatment should include beta-blockers unless these are contraindicated. These drugs reduce the number of ischaemic episodes and probably the risk of myocardial infarction. Nitrates can be a useful adjunctive treatment. They may be given orally, topically or intravenously. The IV dose can be titrated up or down depending on the amount of pain the patient is experiencing and the severity of side effects such as hypotension and headache. The problem of tachyphylaxis with nitrates can be overcome by steady increases in the IV dose if necessary. Calcium antagonists are appropriate treatment for patients intolerant of beta-blockers and may sometimes be added to beta-blockers. Nifedipine, especially in its short-acting form, should not be used for patients with acute coronary syndromes unless they are already taking beta-blockers. Thrombolytic drugs have been disappointing when used for NSTEACS. In trials where they have been used for patients with ischaemic chest pain but without ST elevation there has been a trend towards an adverse outcome. This may be related to the rebound hypercoagulable state that can occur after their use. In general they should not be used for the treatment of NSTEACS. Glycoprotein IIb/IIIa inhibitors (p. 198) should be given for high-risk patients,
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