Myxomas

A 55 year old male presents to the cardiology clinic with intermittent chest pain, shortness of breath, and fatigue over the past few months. He reports palpitations and has experienced several syncopal episodes. He also notes unintentional weight loss of 3 kg over 6 months. Vital signs show blood pressure of 130/80 mm Hg, pulse rate of 110 beats per minute, respiratory rate of 16 breaths per minute, and temperature of 97.2 F. On auscultation, an early diastolic tumor plop followed by a mid diastolic murmur at the apex is heard, mimicking mitral stenosis. The findings vary with body position. Echocardiography reveals a mobile mass attached to the interatrial septum in the left atrium. Diagnosis?

Diagnosis is Atrial myxoma.

1. Definition

Atrial myxoma is the most common primary cardiac tumor in adults, usually arising in the left atrium.

It is histologically benign but functionally malignant due to obstruction and embolization.

2. Etiology

1. Sporadic cases are most common
2. Familial cases are associated with Carney complex
3. Caused by mutation in the PRKAR1A gene

3. Pathophysiology

1. Tumor arises from multipotent mesenchymal cells
2. Typically attached to the interatrial septum near the fossa ovalis
3. Often pedunculated and mobile
4. Ball valve effect causes intermittent mitral valve obstruction
5. Leads to reduced cardiac output and syncope
6. Risk of systemic embolization, including stroke
7. Production of IL 6 leads to constitutional symptoms

4. Clinical Features

4.1 Classic Triad

1. Intracardiac obstruction
2. Embolization
3. Constitutional symptoms

4.2 Obstructive Features

1. Dyspnea
2. Orthopnea
3. Paroxysmal nocturnal dyspnea
4. Syncope due to intermittent obstruction
5. Pulmonary edema in severe obstruction
6. Early diastolic tumor plop
7. Symptoms vary with body position and may worsen when upright

4.3 Embolic Features

1. Stroke is most common
2. Peripheral embolization
3. Occurs in 30 to 40 percent of cases

4.4 Constitutional Features

1. Fever
2. Weight loss
3. Fatigue
4. Due to IL 6 mediated inflammation

5. Diagnosis

5.1 Laboratory Findings

1. Elevated ESR and CRP
2. Anemia of chronic disease
3. Possible leukocytosis

5.2 Electrocardiography

1. Usually nonspecific
2. May show atrial arrhythmias

5.3 Echocardiography

1. Best initial test
2. Shows mobile left atrial mass attached to interatrial septum
3. May prolapse through the mitral valve
4. Transesophageal echocardiography is more sensitive

5.4 Cardiac Imaging

1. Cardiac MRI for detailed characterization

5.5 Coronary Angiography

1. Performed preoperatively in older patients

6. Management

1. Urgent surgical resection is the definitive treatment
2. Required due to risk of embolization and sudden obstruction
3. Excellent prognosis after removal
4. Recurrence is rare, higher in familial cases

7. Associated Condition

Carney complex

1. Lentigines
2. Atrial myxoma
3. Mucocutaneous myxomas
4. Blue nevi
5. Endocrine tumors

8. Key Clinical Insight

Mobile left atrial mass attached to the interatrial septum with positional symptoms, tumor plop, embolic risk, and constitutional features strongly suggests atrial myxoma

9. Exam Level Pearls

1. Most common primary cardiac tumor in adults is atrial myxoma
2. Tumor plop is a characteristic early diastolic sound
3. Symptoms vary with position due to ball valve obstruction
4. Mimics mitral stenosis but with positional variability
5. Requires urgent surgical removal to prevent embolic events

Testicular Torsion

A 21 year old male presents to the emergency department with sudden onset severe testicular pain that began 6 hours ago while playing basketball. The pain is acute, severe, and localized to the right testicle. He also reports nausea. On examination, the right hemiscrotum is swollen, erythematous, and tender. The cremasteric reflex is absent, which is highly suggestive of torsion. The affected testis may appear high-riding with a horizontal lie. Vital signs show blood pressure of 110/80 mm Hg, pulse rate of 88 beats per minute, respiratory rate of 16 breaths per minute, temperature of 96.7°F, and oxygen saturation of 98 percent on room air. Doppler ultrasonography shows absence of testicular blood flow. Diagnosis?

Diagnosis is Testicular Torsion.

1. Definition

Testicular torsion is a urological emergency caused by twisting of the spermatic cord, leading to testicular ischemia.

2. Etiology

1. Bell clapper deformity due to abnormal fixation of the testis to the tunica vaginalis
2. Leads to horizontal lie of the testis
3. Often triggered by physical activity or minor trauma

3. Pathophysiology

1. Twisting of the spermatic cord causes venous obstruction, followed by arterial compromise
2. Results in ischemia and potential infarction of the testis

4. Clinical Features

1. Sudden onset severe unilateral testicular pain
2. Scrotal swelling and erythema
3. Nausea and vomiting may be present
4. Absent cremasteric reflex
5. High-riding testis with horizontal lie

5. Diagnostic Evaluation

5.1 Clinical Diagnosis

1. Primarily a clinical diagnosis
2. Do not delay surgery for imaging if suspicion is high

5.2 Doppler Ultrasonography

1. Shows absent or reduced blood flow

6. Key Diagnostic Insight

Sudden testicular pain + absent cremasteric reflex = testicular torsion

7. Complications

1. Testicular infarction
2. Testicular atrophy
3. Infertility

8. Management

8.1 Emergency Management

1. Immediate surgical detorsion and bilateral orchiopexy

8.2 Time Sensitivity

1. Best outcomes if treated within 6 hours
2. Risk of irreversible damage increases after 6 to 12 hours

8.3 Manual Detorsion

1. May be attempted if surgery is not immediately available
2. Typically performed with medial to lateral rotation
3. Should not delay definitive surgical management

8.4 Non-viable Testis

1. Orchiectomy if the testis is not viable

9. Key Clinical Insight

Time is testis, early intervention is critical to salvage viability

10. Exam Level Pearls

1. Absent cremasteric reflex is highly suggestive
2. Bell clapper deformity is the underlying cause
3. Doppler shows absent blood flow
4. Always perform bilateral orchiopexy
5. Do not delay surgery in high clinical suspicion

Guillain-Barré syndrome (GBS)

 A 42 year old male presents to the emergency department with progressive weakness in both legs and tingling in the feet over the past 4 days. The weakness has ascended over the past 24 hours, now involving the arms and causing difficulty swallowing. He reports an episode of bloody diarrhea 2 weeks earlier after consuming poultry, suggestive of Campylobacter jejuni infection. On examination, there is bilateral symmetric weakness (MRC 3/5) with absent deep tendon reflexes. Cerebrospinal fluid analysis shows elevated protein with normal cell count. Electrophysiologic studies demonstrate prolonged latency and decreased conduction velocity, consistent with a demyelinating pattern. MRI of the brain and spinal cord is normal. Diagnosis?

Diagnosis is Guillain-Barré syndrome following Campylobacter jejuni infection.

1. Definition

Guillain-Barré syndrome (GBS) is an acute immune-mediated polyradiculoneuropathy and a neurologic emergency, characterized by rapidly progressive symmetric weakness and areflexia.

2. Etiology

1. Preceded by infection in approximately 70 percent of cases
2. Most common trigger is Campylobacter jejuni
3. Other associated infections include:
1. Cytomegalovirus
2. Epstein-Barr virus
3. Mycoplasma pneumoniae
4. HIV
5. Zika virus
6. Hepatitis E virus
4. Noninfectious triggers include:
1. Surgery
2. Autoimmune disorders
3. Malignancy
4. Medications

3. Pathophysiology

1. Molecular mimicry between microbial antigens and peripheral nerve gangliosides
2. Formation of antiganglioside antibodies
3. Activation of complement and macrophages
4. Leads to immune-mediated demyelination

4. Clinical Features

1. Ascending symmetric weakness starting in lower limbs
2. Areflexia or hyporeflexia
3. Distal paresthesias
4. Back or radicular pain

4.1 Cranial Nerve Involvement

1. Facial weakness
2. Dysphagia
3. Ophthalmoplegia in variants

4.2 Autonomic Dysfunction

1. Arrhythmias
2. Labile blood pressure
3. Urinary retention
4. Ileus
5. Symptoms typically begin about 10 days after infection and reach nadir within 2 to 4 weeks

5. Diagnosis

5.1 Clinical

1. Progressive bilateral weakness
2. Reduced or absent reflexes

5.2 CSF

1. Albuminocytologic dissociation
1. Elevated protein
2. Normal cell count
2. Protein may be normal in the first week

5.3 Electrophysiology

1. Demyelinating pattern (AIDP)
1. Decreased conduction velocity
2. Prolonged latency
2. Early studies may be normal, requiring repeat testing

5.4 MRI

1. Usually normal
2. May show nerve root enhancement

6. Management

6.1 Indications for ICU Monitoring

1. Rapid progression
2. Bulbar dysfunction
3. Respiratory compromise
4. Autonomic instability

6.2 Immunotherapy

1. IVIG or plasmapheresis (equally effective)
2. Do not combine therapies
3. Corticosteroids are not beneficial

6.3 Respiratory Monitoring

1. Forced vital capacity (FVC)
2. 20/30/40 rule

7. Supportive Care

1. Respiratory support if needed
2. DVT prophylaxis
3. Physical and occupational therapy
4. Prevention of pressure ulcers and aspiration

8. Complications

1. Respiratory failure
2. Autonomic instability
3. Arrhythmias
4. Aspiration pneumonia
5. Deep vein thrombosis and pulmonary embolism

9. Prognosis

1. More than 50 percent fully recover within 1 year
2. About 80 percent regain independent ambulation
3. Mortality is 3 to 7 percent, higher in severe cases

10. Key Clinical Insight

Ascending weakness + areflexia + recent diarrheal illness + albuminocytologic dissociation = Guillain-Barré syndrome

11. Exam Pearls

1. Campylobacter jejuni is the most common trigger
2. Areflexia is the hallmark
3. CSF protein may be normal early
4. IVIG equals plasmapheresis in efficacy
5. Steroids are not useful
6. Autonomic dysfunction can be life-threatening
7. Progression beyond 4 weeks suggests alternative diagnosis such as CIDP