Medical Image of the Month: Superior Vena Cava Syndrome

Figure 1. Large mediastinal lymph nodes (red arrow) causing compression of the superior vena cava (blue arrow). Numerous enlarged lymph nodes can also be seen in the axillary, cervical, and upper abdominal regions (green arrows).

History: A 74-year- old man with a history of diastolic heart failure, chronic kidney disease (CKD), and chronic lymphocytic leukemia (CLL) presented with a complaint of dyspnea. He has had several hospitalizations in the last year for heart failure exacerbation and his home bumetanide was recently increased from twice to three times daily due to persistently increasing weight. His CLL was diagnosed two years prior and treatment was stopped three months ago due to side effects. In the emergency department he reported three weeks of worsening dyspnea especially when lying flat, as well as increased swelling in his legs, abdomen, arms, and face. His weight was up to 277lbs from 238lbs the month before. His diuretics were transitioned to IV, but over the next few days he remained clinically volume overloaded. A noncontrast chest CT was obtained to help evaluate his ongoing respiratory distress (Figure 1). It demonstrated innumerable lymph nodes involving the cervical, axillary, mediastinal, and upper abdominal regions, which had significantly increased in size and number from prior exam several months before. The CT also showed several particularly bulky lymph nodes which appeared to be compressing the superior vena cava.

Discussion: The superior vena cava (SVC) is responsible for about one-third of the venous return to the heart. Because of its thin walls relative to arterial vasculature, it is susceptible to compression from adjacent structures which may subsequently impair venous return to the heart, a process known as SVC syndrome. Intrathoracic malignancy is responsible for 60-85% of cases of SVC syndrome, and common symptoms include facial or neck swelling, swelling of the arms, and dyspnea (1). In this case, the patient’s apparent resistance to diuresis was felt to be partially secondary to SVC syndrome. In stable patients, contrast-enhanced CT is the preferred imaging modality if SVC syndrome is suspected, which can define the extent of SVC blockage. Duplex ultrasound may be used first to exclude thrombus. In this patient with acute kidney injury on CKD it was decided to forgo the contrast study to avoid further kidney damage. Management of SVC syndrome depends on severity, with emergent treatment focused on maintaining the airway and endovenous recanalization. Definitive treatment is directed at the underlying cause (2).

After about a week of aggressive IV diuresis, the patient’s breathing and volume status improved and he was transitioned back to oral diuretics. He was discharged home with plans for hospice.

Matthew R. Borchart MD, Daniel Yu MD, and Indrajit Nandi MD

University of Arizona College of Medicine, Phoenix

Phoenix, AZ USA

References

1. Rice TW, Rodriguez RM, Light RW. The superior vena cava syndrome: clinical characteristics and evolving etiology. Medicine (Baltimore). 2006 Jan;85(1):37-42. [CrossRef] [PubMed]
2. Wilson LD, Detterbeck FC, Yahalom J. Clinical practice. Superior vena cava syndrome with malignant causes. N Engl J Med. 2007 May 3;356(18):1862-9. [CrossRef] [PubMed]

Cite as: Borchart MR, Yu D, Nandi I. Medical Image of the Month: Superior Vena Cava Syndrome. Southwest J Pulm Crit Care. 2020;21(6):136-7. doi: https://doi.org/10.13175/swjpcc060-20 PDF

Medical Image of the Week: Pulsus Alternans

Figure 1. Telemetry display including arterial pressure waveform, which demonstrates alternating beats of large (large arrows) and small (small arrows) pulse pressure. Concurrent pulse oximetry could not be performed at the time of the image due to poor peripheral perfusion.

A 52 year old man with a known past medical history of morbid obesity (BMI, 54.6 kg/m²), heart failure with preserved ejection fraction, hypertension, untreated obstructive sleep apnea, and obesity hypoventilation syndrome presented with increasing dyspnea over several months accompanied by orthopnea and weight gain that the patient had treated at home with a borrowed oxygen concentrator. On arrival to the Emergency Department, the patient was in moderate respiratory distress and hypoxic to SpO2 70% on room air. Physical examination was pertinent for pitting edema to the level of the chest. Assessment of jugular venous pressure and heart and lung auscultation were limited by body habitus, but chest radiography suggested pulmonary edema. The patient refused aggressive medical care beyond supplemental oxygen and diuretic therapy. Initial transthoracic echocardiography was limited due to poor acoustic windows but suggested a newly depressed left ventricular ejection fraction (LVEF) of <25%. The cause, though uncertain, may have been reported recent amphetamine use. The patient deteriorated, developing shock and respiratory failure; after agreeing to maximal measures, ventilatory and inotropic/vasopressor support was initiated.

Shortly after placement of the arterial catheter, the ICU team was called to the bedside for a change in the arterial pressure waveform (Figure 1), which then demonstrated alternating strong (arrow) and weak beats (arrow head) independent of the respiratory cycle. The waveform was recognized as pulsus alternans. Repeat bedside echocardiography suggested severe biventricular systolic impairment and LVEF of approximately 5-10%, later confirmed by formal transesophageal ehocardiography performed prior to a cardioversion for atrial flutter.

Pulsus alternans was first formally described in 1872 and associated with severe left ventricular systolic dysfunction (1). The pattern of pulsus alternans is detectable by palpation, arterial pressure waveform analysis, and Doppler echocardiography. Competing theories in the early 20^th century attempted to explain this finding. Wenkebach and Straub, using the Starling relationship, suggested that the alternating force of the pulse is due to alternating filling volumes: greater diastolic volumes accommodated by increased fiber length caused forceful contraction/greater stroke volume with subsequently reduced end systolic and therefore end diastolic volumes for the next (weaker) beat; the consequently reduced force left again greater end systolic and end diastolic volumes for the next (more powerful) beat thereafter. Gaskell, Hering, and Wiggers alternatively proposed the phenomenon was rooted in myocardial contractility fluctuations independent of volumes. Laboratory and animal data supported both theories, but seminal clinical work in the 1960s using concurrent ventriculography and ventricular pressure measurements demonstrated that both mechanisms, in fact, occur in different human subjects (2). The second, Starling-independent mechanism is now thought to be due at least in part to delayed intracellular calcium cycling leading to rhythmic fluctuations in excitation-contraction coupling (3).

Regardless of the underlying physiology, the significance of pulsus alternans as a harbinger of severe ventricular dysfunction and poor prognosis has been recognized and unquestioned since its description. This was unfortunately true in the case of our patient, who developed multiorgan failure despite resuscitative efforts and died three days after admission.

Luke M. Gabe, MD

University of Arizona College of Medicine

Department of Internal Medicine

Division of Pulmonary, Allergy, Critical Care and Sleep Medicine

1501 N. Campbell Ave.

Tucson, AZ USA

References

1. Traube L. Ein fall von pulsus bigeminus nebst bemerkungen tiber die lebershwellungen bei Klappenfehlern und über acute leberatrophic. Ber Klin Wschr. 1872;9:185.
2. Cohn KE, Sandler H, Hancock EW. Mechanisms of pulsus alternans. Circulation. 1967 Sep;36(3):372-80. [CrossRef] [PubMed]
3. Euler DE. Cardiac alternans: mechanisms and pathophysiological significance. Cardiovasc Res. 1999 Jun;42(3):583-90. [CrossRef] [PubMed]

Cite as: Gabe LM. Medical image of the week: pulsus alternans. Southwest J Pulm Crit Care. 2016;13(5):266-7. doi: https://doi.org/10.13175/swjpcc123-16 PDF 

Medical Image of the Week: Left Ventricular Non-compaction

Figure 1. Cardiac MRI showing severely enlarged and remodeled left ventricle (LV) and moderately enlarged right ventricle (RV) with severe global hypokinesis and akinesis of the interventricular septum. Significant trabeculation was noted in the apical, antero-lateral and anterior segments of the LV (red arrows), consistent with LV non-compaction.

A 38-year-old woman with history of type 2diabetes mellitus and hypertension presented to emergency department with worsening exertional dyspnea and orthopnea for the past 2-3 months. She also reported a 14 pound weight gain within the 2 weeks prior to presentation. She denied any prior history of cardiac or pulmonary disease. Also, there was no family history of heart disease. She denies any recent sick contacts, smoking, alcohol drinking, or substance abuse.

Physical exam revealed jugular venous pressure of 10 cm H₂O and significant bilateral lower extremity pitting edema. Chest x-ray showed an enlarged cardiac silhouette. Brain naturetic peptide (BNP) was 2,917 pg/mL. A subsequent echocardiogram revealed a left ventricular (LV) ejection fraction of 23% with severe global LV hypokinesia with moderate mitral regurgitation. Thyroid panel as well as iron panel were within normal range. Other laboratories were unremarkable. For the new onset systolic heart failure, a coronary angiography was performed, which demonstrated normal coronary arteries. The patient was diagnosed with non-ischemic cardiomyopathy and underwent a cardiac MRI, which showed severely enlarged and remodeled LV and moderately enlarged right ventricle (RV) with severe global hypokinesis and akinesis of the intraventricular septum. Moreover, a significant trabeculation was noted in the apical, antero-lateral and anterior segments of the left ventricle (Figure 1), consistent with “LV non-compaction” without any evidence of LV thrombus. The patient was started on diuretics and safely discharged with significant symptoms improvement.  

LV non-compaction is a cardiomyopathy characterized by altered myocardial wall with prominent left ventricular trabeculae and deep intertrabecular recesses (1). Some authors believe that non-compaction of the ventricular myocardium results from abnormal persistence of the trabecular layer  while others believe that altered regulation in cell proliferation, differentiation, and maturation during ventricular wall formation, resulting in hyper-trabeculation (2). Its prevalence in the general population is unknown but among patients undergoing echocardiography is estimated at 0.014 to 1.3 percent. In patients with heart failure, its prevalence has been reported as 3 to 4 percent (3). Patients with LV non-compaction may present with heart failure, arrhythmias, sudden cardiac arrest, syncope, and thromboembolic events. The diagnosis is usually established by transthoracic echocardiography. When echocardiography is indeterminate, cardiac MRI, computed tomography, or left ventriculography could be an alternative diagnostic modality. Data on treatment of LV non-compaction are limited, and there is no standard therapy established for this condition. Medical management depends on the clinical manifestations, LV ejection fraction, presence of arrhythmias, and risk of thromboembolism.

Rostam Khoubyari MD^1,2 and Seongseok Yun MD PhD³

¹Department of Cardiology, ²Sarver Heart Center; and the ³Department of Medicine, University of Arizona

Tucson, AZ USA

References

1. Maron BJ, Towbin JA, Thiene G, et al. Contemporary definitions and classification of the cardiomyopathies: an American Heart Association Scientific Statement from the Council on Clinical Cardiology, Heart Failure and Transplantation Committee; Quality of Care and Outcomes Research and Functional Genomics and Translational Biology Interdisciplinary Working Groups; and Council on Epidemiology and Prevention. Circulation. 2006 Apr 11;113(14):1807-16. [CrossRef] [PubMed]
2. Henderson DJ, Anderson RH. The development and structure of the ventricles in the human heart. Pediatr Cardiol. 2009 Jul;30(5):588-96. [CrossRef] [PubMed]
3. Kovacevic-Preradovic T, Jenni R, Oechslin EN, Noll G, Seifert B, Attenhofer Jost CH. Isolated left ventricular noncompaction as a cause for heart failure and heart transplantation: a single center experience. Cardiology. 2009;112(2):158-64. [CrossRef] [PubMed]

Cite as: Khoubyari R, Yun S. Medical Image of the week: left ventricular non-compaction. Southwest J Pulm Crit Care. 2016;12(6):229-30. doi: http://dx.doi.org/10.13175/swjpcc036-16 PDF

Medical Image of the Week: Cheyne Stokes Breathing on Polysomnography

Figure 1. A 5-minute epoch showing Cheyne-Stokes breathing (arrow).

A 79-year-old man presented to the sleep lab for a split-night polysomnography (PSG) after a positive Berlin Questionnaire.  He was screened and directly referred to our sleep lab through his PCP.  Patient has a chart documented medical history of atrial fibrillation, idiopathic pulmonary fibrosis, obesity, and CHF. He did not have an echocardiogram available therefore the etiology of his CHF was unclear.  He was found to have severe obstructive sleep apnea and was split early in the night.  Prior to positive airway pressure, his apnea-hypopnea index (AHI) was 77 and were predominantly obstructive hypopneas.  Soon after initiation of positive airway pressure, his PSG revealed the breathing pattern seen in Figure 1.  His respirations exhibited a crescendo-decrescendo pattern (arrow) followed by a period of central apnea consistent with Cheyne Stokes breathing (CSB).  In this patient, CSB was likely due to heart failure, although systolic or diastolic remained unclear.  Of note, he was not on medications found to be responsible for CSB, and did not have a history of cerebral vascular accident. 

Cheyne-Stokes breathing (CSB) is a well-documented but poorly understood abnormal breathing pattern that is believed to be a type of central sleep apnea (CSA), meaning apneas without upper airway obstruction. This compensatory mechanism is characterized by a cyclic change from oscillating events of apnea and hyperpnea. The characteristic feature of CSA-CSB is a longer cycle length, typically 45-60 seconds, alternating with a respiratory phase exhibiting a crescendo-decrescendo pattern of flow. This result is thought to be due to a delay in correction centrally when an elevated arterial PCO2 is detected within the blood stream by chemoreceptors.  Co-morbid conditions often include cardiac disease (primarily heart failure independent of NYHA classification), neurologic disorders, prematurity, or sedation. Diagnosis is made by polysomnography.  Treatment often entails treating the underlying cause or associated disorder.  When all other strategies fail, remaining treatment includes the use of nocturnal continuous positive airway pressure (CPAP), supplemental oxygen, or adaptive servoventilation (ASV).  Although, systolic heart failure with LVEF <45% in patients with predominantly central sleep apnea currently precludes the use of ASV.

Tam Le, MD and Sekhon Kawanjit, MD

Banner University Medical Center Tucson

Tucson, AZ USA

References

1. Cherniack NS, Longobardo GS. Cheyne-Stokes breathing. An instability in physiologic control. N Engl J Med. 1973 May 3;288(18):952-7. [CrossRef] [PubMed]
2. Naughton M, Benard D, Tam A, Rutherford R, Bradley TD. Role of hyperventilation in the pathogenesis of central sleep apneas in patients with congestive heart failure. Am Rev Respir Dis. 1993 Aug;148(2):330-8. [CrossRef] [PubMed]
3. American Academy of Sleep Medicine. International classification of sleep disorders, 3rd ed. Darien, IL: American Academy of Sleep Medicine, 2014.

Reference as: Le T, Kawanjit S. Medical image of the week: Cheyne Stokes breathing on polysomnography. Southwest J Pulm Crit Care. 2016 Apr;12(4):163-4. doi: http://dx.doi.org/10.13175/swjpcc022-16 PDF 

Medical Image of the Week: Cheyne-Stokes Respiration

Figure 1. Cheyne-Stokes Breathing pattern seen. The red arrow indicates the cycle time which is defined as the duration of the central apnea (or hypopnea) + the duration of a respiratory phase.

A 62 year-old male with a past medical history congestive heart failure, chronic obstructive pulmonary disease, and obesity with a body mass index of 38.02 kg/m² underwent an overnight polysomnogram for clinical suspicion for obstructive sleep apnea. He was found to have a periodic breathing as seen in the image above.

Cheyne-stokes respiration (CSR) is a type of periodic breathing characterized by crescendo-decrescendo pattern of respiration separated by central sleep apneas (CSA) or hypopneas (1). CSR-CSA may be seen in up to 15-37% of systolic heart failure patients (2,3). A longer cycle length, usually between 45-90 seconds, as well as the waxing and waning breathing pattern differentiate CSR from other forms of cyclic central apnea. CSA leads to chronically increased sympathetic activity and exerts multiple deleterious effects on the failing heart (2). The presence of CSR has been associated with higher mortality and rapid deterioration in cardiac function (4).

Jared Bartell and Safal Shetty, MD

University of Arizona Medical Center

Tucson, AZ

References

1. Berry RB, Budhiraja R, Gottlieb DJ, Gozal D, Iber C, Kapur VK, Marcus CL, Mehra R, Parthasarathy S, Quan SF, Redline S, Strohl KP, Davidson Ward SL, Tangredi MM; American Academy of Sleep Medicine. Rules for scoring respiratory events in sleep: update of the 2007 AASM Manual for the Scoring of Sleep and Associated Events. Deliberations of the Sleep Apnea Definitions Task Force of the American Academy of Sleep Medicine. J Clin Sleep Med. 2012;8(5):597-619. [CrossRef]  [PubMed]
2. Yumino D, Bradley TD. Central sleep apnea and Cheyne-Stokes respiration. Proc Am Thorac Soc. 2008;5(2):226-36. [CrossRef] [PubMed]
3. Garcia-Touchard A, Somers VK, Olson LJ, Caples SM. Central sleep apnea: implications for congestive heart failure. Chest. 2008;133(6):1495-504. [CrossRef] [PubMed]
4. Hanly PJ, Zuberi-Khokhar NS. Increased mortality associated with Cheyne-Stokes respiration in patients with congestive heart failure. Am J Respir Crit Care Med. 1996;153(1):272-6. [CrossRef] [PubMed] 

Reference as: Bartell J, Shetty S. Medical image of the week: Cheyne-Stokes respiration. Southwest J Pulm Crit Care. 2015;10(3):145-6. doi: http://dx.doi.org/10.13175/swjpcc017-15 PDF

Medical Image of the Week: Cheyne-Stokes Respiration on Overnight Polysomnography

Figure 1. 300 second polysomnogram window showing crescendo-decrescendo pattern of Cheyne-Stokes respiration (solid black arrows). Cycle length is approximately 60 seconds in duration (Outlined black arrows).

A 75 year old man with a significant past medical history of atrial fibrillation, hypertension, complete heart block status-post pacemaker implantation, thoracic aortic aneurysm, and ischemic cardiomyopathy, was referred to the sleep laboratory for evaluation for suspected sleep disordered breathing. The patient had subjective complaints of morning headaches, reported apnea, un-refreshing sleep, nocturnal urination, and intermittent snoring. The diagnostic polysomnogram was significant for periodic breathing, Cheyne-Stokes pattern, with a cycle length that ranged from 60-65 seconds (Figure 1). Oxygen saturation nadir was 79% as measured by pulse oximetry. Electrocardiogram showed a persistently paced rhythm.

Cheyne-Stokes respiration is a periodic breathing pattern characterized by crescendo-decrescendo episodes of respiratory effort that are interspersed between periods of apnea. It is typically seen in individuals with systolic heart failure, but can also be seen in those with intracerebral hemorrhage or infarction. The mechanism for Cheyne-Stokes respiration involves increased central controller gain causing increased central nervous system sensitivity to changes in arterial blood gas PCO₂ and PO₂. Increased circulation time results in circulatory delay between gas exchange occurring at the alveolar capillary membrane and the central chemoreceptors in the medulla. The result is instability in respiration (1).

Ryan Nahapetian, MD, MPH and Sairam Parthasarathy, MD

Pulmonary, Allergy, Critical Care, & Sleep Medicine

University of Arizona, Tucson, AZ

Reference

1. Quaranta AJ, D'Alonzo GE, Krachman SL. Cheyne-Stokes respiration during sleep in congestive heart failure. Chest. 1997;111(2):467-73. [CrossRef] [PubMed]

Reference as: Nahapetian R, Parthsarathy S. Medical image of the week: Cheyne-Stokes respiration on overnight polysomnography. Southwest J Pulm Crit Care. 2014;8(6):328-9. doi: http://dx.doi.org/10.13175/swjpcc055-14 PDF