Sick Sinus Syndrome
Sinus node is the natural pacemaker of the heart which gives out regular electrical pulses to produce each heartbeat. When it is diseased, this function is defective and called sick sinus syndrome.
Sinus node, known in short as SA node, is situated in the right upper part of the heart. Normally it gives out 60 to 100 pulses per minute so that heart beats at the same rate. When you exercise or are having a stress, the rate increases gradually.
When the sinus node stops functioning, it can manifest as a long pause in the ECG, the recording of the electrical activity of the heart.
Just as the next senior person takes charge i...
Source: Cardiophile MD - April 26, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
What is Paradoxical Motion of Interventricular Septum?
Interventricular septum is a common wall shared by the left ventricle and right ventricle. Normally it contracts with the left ventricle, that is why when it does not contract in synchrony with the left ventricle it is known as paradoxical septal motion. The paradoxical motion is due to change in the shape of the left ventricle. Normally the left ventricle is circular in cross section in both systole and diastole. In right ventricular volume overload, septum becomes flat or even concave towards the right ventricle in diastole. This curvature reverts in systole, producing the paradoxical motion. The authors of the cited stu...
Source: Cardiophile MD - April 26, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
What do you call fluid collection around the heart?
Pericardial effusion is collection of fluid within the layers covering the heart. Pericardium is the covering of the heart. It has an inner layer and an outer layer. Fluid collects in between these layers in certain disease conditions and compresses the heart. If the amount of fluid is large or there is a rapid increase in the rate of fluid collection, the compression of the heart prevents its proper filling. An unfilled heart is not able to pump out blood well and the blood pressure falls. This serious condition is known as cardiac tamponade.
Cardiac tamponade needs urgent removal of fluid from the pericardial cavity by n...
Source: Cardiophile MD - April 25, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Which coronary artery is called widow maker artery and why?
Coronary arteries are blood vessels supplying oxygenated blood to the heart muscle. LAD is short for left anterior descending coronary artery. LAD is usually the largest branch of the left main coronary artery which supplies the major portion of the left ventricle.
Hence blockage of LAD can cause a major heart attack, which can sometimes be fatal. That is why LAD has been called a widow maker artery. LAD supplies the front region of the left ventricle and the partition wall between the ventricles. Ventricles are the lower muscular pumping chambers of the heart.
When the LAD is blocked at its origin, the resulting damage to...
Source: Cardiophile MD - April 24, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Treadmill Stress ECG
Treadmill Exercise ECG is usually done with a computerized treadmill unit which controls the motor speed of the treadmill as well as monitors the ECG. ECG is recorded periodically during the test in addition to documenting any specific events like arrhythmias. Ideally treadmill test is done in a basal state so that the process of digestion of food and consequent increase in cardiac output does not interfere with the assessment. If it is a diagnostic test, the individual should be off medications. But if it is for assessment of effort tolerance while on treatment, it may be done on medications.
Though various protocols like...
Source: Cardiophile MD - April 24, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
How Significant is First Degree Heart Block?
First degree heart block is an abnormality in the electrical conduction of the heart noted on the ECG, the recording of the electrical activity of the heart. It is not a block in the blood vessels of the heart which we are more familiar with. The waves on an ECG are P, QRS complex and the T wave.
Normal interval between the onset of the P wave and the onset of QRS complex is up to one fifth of a second (0.2 seconds). When this interval is increased, it is called first degree heart block or first degree atrioventricular or AV block to be specific. Atria are the upper chambers of the heart and ventricles the lower chambers.
...
Source: Cardiophile MD - April 23, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Types of Ventricular Tachycardia
Three or more ventricular beats in a row at a rate above 100 per minute is termed ventricular tachycardia. Ventricular tachycardia lasting more 30 seconds or requiring termination earlier due to hemodynamic compromise is called sustained ventricular tachycardia. Non sustained ventricular tachycardia is one which lasts less than 30 seconds without hemodynamic compromise.
Based on the morphology, ventricular tachycardia can be classifed into monomorphic in which all beats have same morphology on ECG in a given lead and polymorphic in which there is beat to beat variation.
Polymorphic ventricular tachycardia with QT interval ...
Source: Cardiophile MD - April 23, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Difference between pulsed wave and continuous wave Doppler
In pulsed wave Doppler, same piezoelectric crystal is used to transmit and receive the echo from the sample volume. Hence the signals are sent out in pulses and the intervals between the pulses are used to receive the echoes. In continuous wave Doppler, one piezoelectric crystal transmits continuously and another one receives continuously. As the transmission and reception are continuous, it is not possible to find out the depth from which the return signals are received. At the same time continuous wave Doppler can analyze higher velocities while pulsed wave Doppler can analyze only lower velocities.
In case of pulsed Dop...
Source: Cardiophile MD - April 22, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
What is the link between thyroid and heart disease?
Heart disease can occur with both increased function of the thyroid gland and decreased function of the thyroid gland. When thyroid function is increased, heart rate increases and the work load of the heart increases.
In severe cases heart failure may occur. A peculiarity of heart failure associated with increased thyroid function is that it is a high output failure unlike the usual heart failure in which the pumping function of the heart is reduced, and low output failure occurs.
While in low output heart failure the extremities are cold, in high output failure due to increased thyroid function, the extremities of the lim...
Source: Cardiophile MD - April 22, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Fractional flow reserve for guiding coronary intervention and functional SYNTAX score
Coronary angiography gives a visual impression about the severity of the stenosis. But it need not imply the actual functional significance of the stenosis in terms of flow physiology. It is often difficult to decide which are the flow limiting lesions when there are multiple stenoses in same or different territories. It is here that the fractional flow reserve estimation helps.
FFR is estimated using a guide wire with a pressure transducer. FFR wires have properties similar to the floppy guide wires so that they can passed across coronary lesions back and forth easily to assess the pressure drop across the lesions.
The f...
Source: Cardiophile MD - April 22, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Relation Between Stroke and Heart Disease
Stroke is often due to sudden loss of blood supply to a region of the brain which usually results in paralysis of a part of the body. Stroke could also be due to bleeding into a part of the brain.
Strokes and heart disease are linked together in various ways. In general, risk factors for stroke and some forms of heart disease are similar. Strokes due to blocks in blood vessels, can be seen along with blocks in blood vessels of the heart.
Stroke can occur after a heart attack as well. Heart attack damages a part of the heart muscle. This can lead to damage of the inner lining of the heart in that region. A blood clot can fo...
Source: Cardiophile MD - April 21, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
L-type and T-type Calcium Channels
Calcium channels in the heart muscle are of two types: L-type (ICa-L) and T-type (ICa-T). Both these are voltage gated calcium channels. L-type channels are involved in the myocardial contraction while T-type channels are involved in impulse generation and conduction. The calcium channels are located in the plasma membrane and are protein complexes that are voltage gated to regulate entry of calcium ions into the cell.
Phase 2 or plateau phase of myocardial action potential is featured by influx of calcium ions through L-type calcium channels (ICa-L). In addition to myocardial cells, L-type calcium channels are important i...
Source: Cardiophile MD - April 21, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
MCQ on Type 1 Diabetes Mellitus
All of the following are true regarding type 1 diabetes mellitus except:
A. Accounts for about 10% of all cases of diabetes mellitus
B. First peak of presentation occur at 5 to 7 years of age
C. Can occur between 1 and 2 years in high risk groups
D. In all populations, females are significantly more affected
Correct answer: D.
Type 1 diabetes mellitus is slightly more common in boys and men. (https://www.ncbi.nlm.nih.gov/books/NBK441918/) (Source: Cardiophile MD)
Source: Cardiophile MD - April 20, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Potential Risk of Serious Bleeding in Patients With AF Using Diltiazem With Apixaban or Rivaroxaban
A potentially serious drug interaction between diltiazem and apixaban or rivaroxaban has been reported in US Medicare patients taking these drugs together for atrial fibrillation. The study has been published as online ahead of print in the Journal of American Medical Asociation [1]. The study compared serious bleeding risk for new users of apixaban or rivaroxaban with atrial fibrillation treated with diltiazem or metoprolol. It was a retrospective cohort study which included US Medicare benefiaries aged 65 years or more with atrial fibrillation and follow up period was one year. Primary outcome was a composite of bleedi...
Source: Cardiophile MD - April 19, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
Who Needs a CT Coronary Angiogram?
CT coronary angiograms are increasing in popularity as a non-invasive screening test for detecting blocks in coronary arteries.
Coronary arteries are blood vessels supplying oxygenated blood to the heart.
Angiograms are images of blood vessels, usually obtained by injecting medications for contrast from body structures.
CT angiograms are reconstructions from multi slice CT scans following injection of contrast material into a forearm veins.
Veins are blood vessels returning deoxygenated blood to the heart.
CT coronary angiogram can be done as an outpatient test, in the X-ray department.
As of now CT angiograms cannot repla...
Source: Cardiophile MD - April 18, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs
