Pulmonary Circulation Disorders
A 62-year-old woman presents to the emergency department with shortness of breath after a trans-Pacific flight. Computed tomography of the chest shows bilateral proximal pulmonary emboli (PE). She is started on enoxaparin.
What finding would be the strongest indication to administer systemic fibrinolytic therapy in this patient?
The correct answer choice is blood pressure (BP) of 88/64 mm Hg. The use of systemic fibrinolytic therapy in acute PE has been the source of some controversy, especially given the risk of adverse bleeding events. International cardiology and chest guidelines agree, however, that the strongest indication for lytic use is in patients with PE and associated hypotension or shock (e.g., systolic BP of <90 mm Hg).
The other answer choices, especially elevated right ventricular/left ventricular ratio (≥1) and B-type natriuretic peptide level, can be associated with worse outcomes and may prompt consideration of lytic therapy if clinical deterioration occurs after initiation of anticoagulation.
A 68-year-old man with coronary artery disease is traveling on the subway. While awaiting the next train, he suddenly collapses from ventricular fibrillation (VF).
For each minute that cardiopulmonary resuscitation (CPR) and defibrillation are delayed, by how much is the probability of survival diminished?
The correct answer is 7-10%. A common initial rhythm in out-of-hospital cardiac arrest is pulseless ventricular tachycardia or VF. Electrical defibrillation is the most effective way to terminate the rhythm. For every minute that passes from a witnessed cardiac arrest, survival declines by 7-10%. When a bystander performs CPR, the decline is more gradual, reportedly 3-4%.
A 52-year-old woman presents to the clinic for the evaluation of dyspnea. She reports slow worsening in her ability to climb stairs over the previous 6 months. She notes some discomfort and discoloration in her hands, especially in cold weather. She denies orthopnea, paroxysmal nocturnal dyspnea, fevers, chills, or palpitations. She has no known cardiac history and is taking no medication except for a multivitamin.
On examination, her blood pressure is 128/66 mm Hg, resting pulse is 89 bpm, and oxygen saturation is 89% on ambient air. She appears anxious. Facial and periungual telangiectasias are present, and the skin over her fingers appears thickened and tight. Her lung examination is unremarkable except for a few early inspiratory rales. Her jugular venous pressure (JVP) is not elevated, but there is positive hepatojugular reflux. Heart sounds are regular with no murmurs. There is no edema and peripheral pulses are normal.
An electrocardiogram shows normal sinus rhythm. A transthoracic echocardiogram shows normal left ventricular size and function and a slightly enlarged right ventricle (RV) with mild dysfunction. No valvular regurgitation is seen. A chest X-ray reveals no pulmonary edema, although the pulmonary arteries appear larger than expected with diffuse mild "ground glass" opacities.
What echocardiographic findings would be most consistent with this patient's suspected diagnosis?
The correct answer choice is flattening of the interventricular septum.
This patient had cardinal features of systemic sclerosis with related pulmonary hypertension (PH; e.g., normal JVP with positive hepatojugular reflux, RV and right atrial [RA] enlargement, and enlarged pulmonary arteries on chest X-ray). Tricuspid regurgitation (TR) may not always be detected on examination in patients with PH. PH is confirmed if the TR jet velocity is ≥3.4 m/sec. If the TR jet velocity is >2.9 m/sec and there are no other echocardiographic signs of PH, then the probability of PH is intermediate. If the TR jet velocity is ≤2.8 m/sec with no other echocardiographic signs of PH, the probability of PH is low.
In this instance, there is no TR jet, so other echocardiographic signs of PH should be sought. These include ventricular size/function, pulmonary artery changes, and inferior vena cava (IVC)/RA changes. When two or more of these signs are present, the level of probability of PH is elevated. For instance, if the TR jet velocity is ≤2.8 m/sec or no TR jet is present and two of these signs are present, then the probability of PH is elevated to intermediate. If the TR jet velocity is between 2.9-3.4 m/sec and two of these signs are present, then the probability of PH is high.
None of the answer choices meet these criteria except for interventricular septal flattening. Criteria to raise suspicion for PH include an early diastolic pulmonary regurgitation velocity of >2.2 m/sec, an IVC diameter >2.1 cm with <50% inspiratory collapse, or a pulmonary artery diameter >25 mm. A tricuspid annular plane systolic excursion >1.7 cm is consistent with normal RV function.
A 78-year-old man with hypertension and a history of ischemic stroke presents to the cardiac catheterization laboratory for coronary angiography. He has no history of diabetes mellitus, prior coronary artery disease, or tobacco use. He has been experiencing progressive exertional chest pain over the prior 2 months, now present with daily activities. Metoprolol has been titrated to a dose of 100 mg twice daily and isosorbide mononitrate has been titrated to a dose of 60 mg/day without resolution of chest pain. His other daily medications include aspirin 81 mg and atorvastatin 40 mg. He recently underwent an exercise myocardial perfusion imaging stress test that revealed reversible ischemia in the midanterior wall and a left ventricular ejection fraction of 60%. His laboratories prior to catheterization included creatinine 0.8 mg/dL. His vital signs include heart rate 70 bpm and blood pressure 115/75 mm Hg.
Coronary angiography reveals a 95% stenosis of the proximal left anterior descending coronary artery. He undergoes percutaneous coronary intervention (PCI) with a 3.5 x 12 mm drug-eluting stent without complications.
What is the most appropriate next step?
Clopidogrel is the drug of choice (Class I) for patients with stable coronary artery disease undergoing PCI according to both American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology (ESC) guidelines.
The data underlying ticagrelor and prasugrel are derived from acute coronary syndrome trials. Nevertheless, these agents may be considered (Class IIb) in patients with a high ischemic risk and low bleeding risk, as outlined in the ESC guidelines. However, this patient has a history of stroke and is >75 years of age, which are contraindications to the use of prasugrel. Finally, routine platelet function testing to guide antiplatelet therapy before or after elective stenting is not currently recommended by the ACC/AHA or ESC guidelines due to the neutral results of multiple randomized controlled trials.
A 43-year-old woman presents to the emergency department with 2 hours of sudden-onset shortness of breath. She has a history of hypertension. Her medications include amlodipine and a combined estrogen/progesterone oral contraceptive.
On examination, her heart rate is 103 bpm, blood pressure is 114/88 mm Hg, respirations are 22 breaths/min, and oxygen saturation is 94% on ambient air. She appears anxious and mildly dyspneic. Jugular venous pressure is 12 cm H2O, heart sounds are tachycardic but regular, and lungs are clear to auscultation. There is 1+ bilateral pitting edema. An electrocardiogram (ECG) shows sinus tachycardia at 101 bpm and an incomplete right bundle branch block pattern with T-wave inversions in leads V1-V3. Computed tomography (CT) pulmonary angiography reveals occlusive thrombus within the truncus anterior artery supplying the right upper lobe as well as partially occlusive thrombus within the left pulmonary artery. The right ventricular/left ventricular (RV/LV) ratio on CT is 0.94.
What is the most appropriate therapy at this time?
The correct answer choice is weight-adjusted enoxaparin. This patient is presenting with an intermediate-risk pulmonary embolism (PE) given signs of RV enlargement (RV/LV ratio >0.9 on CT) but hemodynamic stability. Thrombolytics and aspiration thrombectomy are generally reserved for hemodynamically unstable patients (those with "massive" or "high-risk" PE) or for patients with intermediate-risk PE with subsequent clinical deterioration.
Percutaneous catheter-directed treatment may be used in patients with high-risk PE with contraindications to thrombolysis or in whom thrombolysis has failed.
A 50-year-old man with nonischemic cardiomyopathy and severe left ventricular (LV) systolic dysfunction (LV ejection fraction 15%) is admitted to the cardiac care unit with cardiogenic shock after presenting 24 hours earlier from home with dyspnea and progressive respiratory failure. His admission physical examination was notable for severely elevated jugular venous pressure, extensive peripheral edema, and bilateral wet rales; blood pressure (BP) was 75/60 mm Hg and heart rate was 115 bpm. A chest X-ray is consistent with cardiogenic pulmonary edema.
He was initially placed on dobutamine titrated to a dose of 7.5 mcg/kg/min and a furosemide infusion at 20 mg/hour. Laboratory studies revealed acute renal injury with creatinine (Cr) 2.5 mg/dL (baseline 1.5 mg/dL) and elevated liver enzymes with aspartate aminotransferase and alanine aminotransferase both >800 U/L. Serum lactate was 4 mmol/L.
After 24 hours, he remains hypotensive (BP 80/60 mm Hg) with Cr 2.5 mg/dL, lactate 4.5 mmol/L, and urine output <1 L over 24 hours. Milrinone 0.25 mcg/kg/min is added with little change in BP or urine output over the subsequent 6 hours. He has been on bilevel positive airway pressure since admission with escalating oxygenation requirements, and ultimately requires intubation with ventilator requirements of fraction of inspired oxygen 50% and positive end-expiratory pressure 15 cm H2O.
Following stabilization after intubation, a right heart catheterization reveals right atrial (RA) pressure 20 mm Hg, pulmonary artery pressure 40/25 mm Hg, pulmonary capillary wedge pressure 25 mm Hg, cardiac output 3.6 L/min, and cardiac index (CI) 1.8 L/min/m2. His BP is 80/50 mm Hg.
What is the most appropriate form of circulatory support for this patient?
This is a patient with cardiogenic shock and evidence of biventricular heart failure. He has shock refractory to inotropic support with low cardiac index (CI) and rising lactate. Urgent temporary mechanical circulatory support is needed. Circulatory support of only the left heart will be inadequate in this patient who has evidence of right-sided heart failure with markedly elevated RA pressure. In addition, the patient is demonstrating worsening oxygenation requirements, leading to intubation with refractory hypoxemia despite maximal oxygenation support via the ventilator. Thus, the patient needs biventricular mechanical support that can also improve oxygenation; venoarterial extracorporeal membrane oxygenation (ECMO) is this form of support.
The other answer choices will either not support the right heart failure (intra-aortic balloon pump, percutaneous LV assist device) or not support the left heart failure (venovenous ECMO, percutaneous right ventricular assist device). Additionally, the next therapeutic destination in this patient's care will need to be determined: transplantation, durable mechanical circulatory support, or recovery.
A 68-year-old woman with a 15-year history of scleroderma notes progressive shortness of breath with exertion and decreased exercise tolerance for the prior several months.
On physical examination, her blood pressure is 116/92 mm Hg and heart rate is 92 bpm. She has an increased P2 sound with a grade 2/6 holosystolic murmur increased with inspiration and 2+ pitting edema of her lower extremities. Her yearly pulmonary function test shows a significant decrease in her diffusing capacity for carbon monoxide. Echocardiography demonstrates an enlarged right ventricle (RV) with depressed RV function, tricuspid regurgitation (TR) jet 4 m/sec, and left ventricular ejection fraction 55%.
What is the best next step in her management?
Patients with longstanding scleroderma have a significant risk of pulmonary hypertension (PH), which often presents with dyspnea on exertion and evidence of PH on physical examination (loud P2, TR, and pedal edema). If the echocardiogram suggests the diagnosis of PH, a right heart catheterization should be undertaken to confirm the diagnosis.
If the echocardiogram does not show evidence of PH, other causes of dyspnea should be entertained based on the clinical scenario, including stress testing or computed tomography (CT) coronary angiography to assess for coronary artery disease, ventilation/perfusion scanning to assess for pulmonary embolism, and/or high-resolution CT scanning to assess for interstitial lung disease. Anti-Scl 70 antibodies are not useful in the diagnosis of scleroderma-associated PH.
A 53-year-old woman is brought by ambulance to the hospital after being a restrained driver in a motor vehicle collision. She reports chest and arm pain with bruising over those areas. She has no known past medical history. Her vitals on presentation are blood pressure 116/78 mm Hg and heart rate 102 bpm. Examination is notable for multiple ecchymoses. Lungs are clear to auscultation. Heart sounds are regular with no murmurs heard. Electrocardiography (ECG) shows sinus tachycardia. Laboratory values include hemoglobin of 10.8 g/dL and troponin I of 0.05 ng/mL (normal <0.02 ng/mL). A focused assessment with sonography for trauma (FAST) ultrasound shows normal left ventricular function and no pericardial effusion. A computed tomography (CT) chest/abdomen/pelvis reveals rib fractures and a pulmonary contusion.
The patient is admitted to the trauma service. Six hours later, her blood pressure is 86/64 mm Hg and heart rate is 128 bpm. ECG shows sinus tachycardia with diffuse 0.5 mm ST depressions. Repeat laboratory values are hemoglobin 10.6 g/dL and troponin I 0.08 ng/mL.
What is the best next step in her management?
This patient has suffered severe blunt chest trauma. She is at increased risk for traumatic cardiac complications such as pericardial effusion, ventricular septal or free wall rupture, and acute valvular dysfunction. Although she had an initial negative FAST study, patients with persistent or worsening hypotension or shock should have a transthoracic echocardiogram for further evaluation, as findings can be missed on a FAST study and some of these injuries can evolve over time.
Although her ECG shows some evidence of mild ST depression (likely due to tachycardia and potential demand ischemia), the clinical presentation and troponin trend do not appear consistent with an acute coronary syndrome for which coronary angiography should be pursued before other diagnostic workup. Similarly, heparin infusion would be not be appropriate in this patient with acute chest trauma and increased bleeding risk without a clear indication. Metoprolol would be contraindicated in a patient with impending shock. A CT chest/abdomen/pelvis should not be the first study for a patient with chest trauma and hemodynamic instability, but it could be considered pending further evaluation.
A 52-year-old man presents to your office for the evaluation of dyspnea on exertion for the prior 6 months. One year prior, he was diagnosed with a left femoral deep vein thrombosis in the setting of a long plane ride and received 3 months of anticoagulation therapy with rivaroxaban. He has no other medical problems and takes no medications.
On examination, his heart rate is 98 bpm, blood pressure is 110/70 mm Hg, and oxygen saturation is 92% on room air. Jugular venous pressure is 10 cm H2O with prominent v waves. Lungs are clear. Heart sounds are regular with a right-sided S3 gallop and a grade 2/6 systolic murmur that increases on inspiration. Extremities are warm with left leg venous varicosities and no edema. Echocardiography shows an enlarged right ventricle with severely reduced systolic function and severe tricuspid regurgitation. Estimated right ventricular systolic pressure is 64 mm Hg.
In addition to a ventilation/perfusion (V/Q) scan, what should be checked?
The correct answer choice is antiphospholipid antibodies.
Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease of obstructive pulmonary artery remodeling as a consequence of major vessel thromboembolism. It is unknown why some patients with acute pulmonary embolism (PE) develop CTEPH and others do not. Several studies suggest that an underlying hypercoagulable state may be responsible. Patients who report new or persistent dyspnea or exercise intolerance after 3 months of anticoagulant treatment for PE should undergo targeted diagnostic tests. If CTEPH is suspected, a V/Q scan remains the first-line imaging modality for CTEPH given the >95% sensitivity and specificity for the diagnosis. Patients with CTEPH should also undergo thrombophilia screening, including for the presence of antiphospholipid antibodies; this is the correct answer choice.
The other antibodies listed (antinuclear, anti–double-stranded DNA, and anticentromere) are observed in connective tissue diseases, and antinuclear cytoplasmic antibodies are observed in vasculitis. These conditions can be associated with pulmonary hypertension but would not be consistent with the patient's presentation of antecedent deep vein thrombosis and likely unrecognized PE. In this man, an underlying hypercoagulable state with persistent symptoms from CTEPH should be suspected.
A 34-year-old woman is 30 weeks pregnant and is referred to your clinic for elevated blood pressure. This is her first pregnancy. At her most recent obstetrics visit, her systemic blood pressure was 150/75 mm Hg. A urinalysis was negative for protein, but positive for glucose. Further testing was consistent with gestational diabetes mellitus. She was started on labetalol 100 mg twice a day by her obstetrician with normalization of her blood pressure to 115/78 mm Hg.
Her cardiac examination is normal except for an S3. You make no changes in her medical regimen.
She returns feeling well after delivery of a healthy baby girl. Her blood pressure on return is 128/78 mm Hg and pulse is 75 bpm. Her entire examination is unremarkable. She relates that her father and two uncles had coronary interventions, and her maternal grandfather had a stroke at 80 years of age. She has never smoked cigarettes and leads an active lifestyle. She no longer needs the beta-blocker for blood pressure control.
What is her risk of future cardiovascular (CV) events given her pregnancy-associated complications?
The correct answer choice is that her risk of hypertension, coronary artery disease, and stroke are increased twofold. Women with an history of pregnancy-related hypertension disorders, gestational diabetes mellitus, preterm birth, placental abruption, and stillbirth are at increased risk for future CV disease compared with women with no history of these pregnancy complications.
Gestational diabetes mellitus, pre-eclampsia, preterm birth, small-for-gestational-age birth weight, intrauterine growth restriction, and stillbirth have been postulated to be a result of placental and/or vascular dysfunction due to increased inflammation and subsequent oxidative stress and mitochondrial dysfunction. As a result of their shared mechanisms of action, many of these complications may be related, and their co-occurrence may confer a greater risk for maternal CV disease.