Acute Pericarditis - Pericardial Rub

Pericardial rub is highly specific for acute pericarditis. In addition to a patient's history and investigations, I learned the importance of identifying pericardial friction rubs on physical exam.

The pericardial rub is produced when the heart rubs against the pericardium. There are 3 phases to this caused by the three largest movements of the heart:

1. Ventricular systole
2. Ventricular diastole
3. Atrial systole

This tri-phasic pericardial rub is pathognomonic for acute pericarditis. Unfortunately, a monophasic pericardial rub is the most commonly identified on physical exam. 

Other important characteristics of the pericardial rub:
1. Transient
2. Loudest over the LLSB
3. Better detected with forward leaning and forced expiration

-BH-

Resources:
1. Harvey teaching

Physical Exam: Aortic Stenosis

Through Harvey teaching, I learned key findings in the physical examination of aortic stenosis. 

Cardinal symptoms of AS: dyspnea and other symptoms of heart failure, angina, and syncope

Findings specific for AS:
- Pulsus parvus et tardis
- Apical-carotid delay
- Radial-brachial delay
- Late-peaking systolic murmur
- Absent or soft S2 sound due to calcification of aortic valves

Murmur characterization:
- Systolic
- Late-peaking
- Harsh
- Loudest over second right intercostal space
- Radiates to carotid arteries

-BH-

Resources:

1. Harvey teaching
2. Aortic Stenosis: Diagnosis and Treatment (AAFP)

How To: JVP

 How To: JVP

It was great to receive a refresher on how to do the JVP examination during my rotation. We all know how to do the basic steps, but breaking each step down even further helped me better understand how the JVP is used and what it can tell us.

One: Identify the JVP

In comparison to the carotid pulse, the JVP can be distinguished by six unique features.

1. Location is between the two heads of the sternocleidomastoid muscles

2. Multiphasic waveform

3. Not palpable

4. Occludable

5. Changes with position and respiration - decrease with respiration

6. Changes with abdominojugular reflux maneuver

Two: Absolute Height

A normal JVP is <4cm. An elevated JVP is suggestive of volume overload, but more specifically, poor RV compliance.

Three: Abdominojugular Reflux

This maneuver is performed by applying 20-30mmHg of pressure to the patient’s abdomen. A normal response is an elevation of the JVP 2-4cm above the baseline level, and return to baseline within 10 seconds. A 2cm (70% specificity)/4cm (90% specificity) AND sustained elevation >10 seconds are required for a positive AJR exam.

Four: Waveform Analysis

Ascent

a: atrial contraction

c: bulging of tricuspid with ventricular contraction

v: passive atrial filling

cv: specific for tricuspid regurgitation

Descent

x’: downward movement of tricuspid with ventricular contraction

y: atrial emptying with opening of tricuspid

-BH-

Reference:

1. Harvey teaching

2. Drawing by me

Intro to Polycythemia

On my first day in Ambulatory GIM clinic, I met with a patient referred for polycythemia. Although he had a clear history of OSA, which may explain his BW findings of erythrocytosis, I reviewed the other causes of polycythemia for a comprehensive, thorough investigation of my patient's BW findings.  

Definition: an abnormal elevation of hemoglobin and/or hematocrit in peripheral blood.

a) Increased Hb: >10.3mmol/L (men) or >10.0mmol/L (women)

b) Increased hematocrit: >49% (men) or >48% (women)

Causes:

1) Primary Polycythemia
Caused by mutation in RBC progenitor cells that leads to increased RBC mass, most commonly polycythemia vera or another myeloproliferative neoplasm.

2) Secondary Polycythemia from elevated serum EPO

a) Hypoxia-associated:
- Cardiopulmonary disease such as chronic pulmonary disease, cyanotic heart disease, obstructive sleep apnea.
- High altitude
- Decreased release of oxygen to tissues from high oxygen affinity hemoglobin, such as CO toxicity.
- Smoking
- Diminished oxygen sensing by the kidneys can cause increased EPO production, including renal artery stenosis

b) Tumor-associated:
- Hepatocellular carcinoma
- Renal cell carcinoma
- Hemangioblastoma
- Pheochromocytoma
- Uterine myomata

History:

- Hyperviscosity symptoms: chest/abdominal pain, myalgia, weakness, fatigue, headache, blurred vision
- Thrombosis or bleeding
- Other symptoms: unexplained fever, sweats, weight loss, gout, erythromelalgia
- Social history: smoking, exposure to CO
- Family history

Investigations:
1. Pulse oximetry
2. Serum EPO
3. Electrolytes
4. Kidney and LFTs
5. Consider JAK2 genetic testing 
6. Consider CXR, abdominal U/S

-BH-

Resource: Diagnostic approach to the patient with polycythemia (uptodate)