PCL 1 Differential Diagnosis

Diagnosis is evaluated according to

• medical history
• physical examination
• electrocardiogram (ECG)
• echocardiogram/cardio echo--> This test is performed to identify heart valve problems, to check ventricular function, or to look for blood clots in the atria.

The different diagnosis for this week are:
1. Atrial Fibrillation
2. Atrial Flutter
3. Supraventricular Tachycardia
4. Wolff-Parkinson-White Syndrome

Symptoms of Atrial Fibrillation

• heart palpitation
• irregular pulse
• dyspnoea
• weakness, fatigue
• dizziness, confusion
• light-headedness, syncope
• chest pain, angina

Symptoms of Atrial Flutter

• Some patients may have no symptoms at all
• palpitations (rapid heart beat)
• "fluttering" or tremor feeling in the chest
• shortness of breath
• anxiety
• People with underlying heart or lung disease who experience atrial flutter may have these and other, more significant symptoms.
• Angina pectoris (chest or heart pains)
• feeling faint or light-headed
• fainting (syncope)

Differences between A. Fibrillation and A. Flutter

• During atrial fibrillation, the atrial rhythm is irregular, so the ventricular rhythm is also irregular. During atrial flutter, the atrial rhythm is regular, and the ventricular rhythm may be regular or irregular.
• In patients with atrial fibrillation, the pulse is irregular and usually fast. In people with atrial flutter, the pulse is more likely to be regular and fast
• Occasionally, atrial flutter is detected in people with no symptoms when they see their health care provider for another reason. The health care provider may notice unusual heart sounds or an unusual pulse on physical exam, and he or she may order and ECG.

Exams and Tests

• Upon hearing about the symptoms, the health care provider may suspect an arrythmia
  
• Because many different arrhythmias can cause similar symptoms, the evaluation at first focuses on ruling out the most dangerous ones. One simple test of ECG can tell a lot about what is happening with the heart.

Paroxysmal supraventricular tachycardia (PSVT)

Paroxysmal supraventricular tachycardia (PSVT) is an occasional rapid heart rate. "Paroxysmal" means from time to time.

Alternative Names

PSVT; Supraventricular tachycardia

Causes

Normally, the atria and ventricles of the heart contract in a coordinated manner. The contractions are caused by an electrical signal that begins in an area of the heart called the sinoatrial node (also called the sinus node or SA node). The signal moves through the atria and tells the atria to contract.

PSVT starts with events taking place above the lower heart chambers (ventricles). PSVT can be initiated in the SA node, in the upper heart chambers (atria), in the atrial conduction pathways, or other areas.

PSVT can occur with digitalis toxicity and conditions such as Wolff-Parkinson-White Syndrome

The condition occurs most often in young people and infants.

The following increase risk for PSVT:

• Alcohol use
  

• Illicit drug use
• Smoking
• Caffeine use
  

Symptoms

• Chest tightness
• Anxiety
• Rapid Pulse
• Palpitations
• Shortness of breath
• Dizziness
• Fainting
  

To confirm that our patient has A Fibrillation and not Supraventricular Tachycardia,

• ST occurs most often in young people and infants ( Our patient was a 66 years old man)
• The ECG reading shows narrow QRS complexes with P waves at a ration of P:QRS = 2:1 (Our patient's ECG showed no P waves)

Wolff-Parkinson-White Syndrome

• A syndrome of pre-excitation of the ventricles of the heart due to an accessory pathway known as the bundle of Kent.
• This accessory pathway is an abnormal electrical communication from the atria to the ventricles
• It is an abnormality in the electrical functioning of the heart which may cause rapid heart rates that affects the electrical signal between the atria and the ventricles.

Causes-How it happens

• congenital heart disease may contribute to this and other arrhythmias
• Ebstein's anomaly, a congenital heart defect that involves displacement of the tricuspid valve, located on the right side of the heart, is one known cause of WPW syndrome.
• Often, there is no known cause for WPW syndrome and many patients are aymptomatic.

Features of its ECG

• The ECG shows short PR interval, less than 3 squares (120ms)
• Slurred upstroke to the QRS indicating pre-excitation (delta wave)
• Broad QRS
• Secondary ST and T waves changes
  

During examination, the patients' heartbeat goes greater than 230 bpm.

By Irene & Tin Yee


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