Case of the Week: February 11-February 18, 2016

Middle-aged women with chronic heart failure

Identify the annotated medical device. What is it and what is its purpose? Is the device MRI conditional or not?

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Case Details

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Radiologic Findings PA (Fig. 1A) and edge-enhanced frontal (Fig. 1B) chest radiographs show a left subclavian transvenous approach atrial-ventricular ICD with appropriately positioned leads. There is also evidence of a remote sternal splitting thoracotomy and aortic valve replacement with cardiomegaly and pulmonary artery enlargement consistent with pulmonary hypertension. The vascular clarity is diminished and there is mild cephalization of blood flow reflective of mild heart failure. The lungs are otherwise clear. The annotation on the frontal (Fig. 1A-B) and lateral (Fig. 2) chest radiographs highlights a wireless metallic sensor device deployed in the left pulmonary artery circuit and in the posterior basilar artery in particular.

Answer

Diagnosis: CardioMEMS™ PA Sensor

Differential Diagnosis

None

Discussion

Heart failure affects about 6 million Americans annually, with about 670,000 new cases diagnosed each year. The management of chronic heart failure often includes weight and blood pressure control, pharmacotherapy and sometimes deployment of a cardiac resynchronization therapy device (CRT).

Heart failure has many underlying causes. Coronary artery disease (CAD) is responsible for about half of all cases. Other possible causes may include but are not limited to: untreated or uncontrolled hypertension, atrial fibrillation, cardiac valvular disease, congenital heart disease, diabetes and various cardiac infections. Pulmonary artery pressures serve as a good clinical marker of the severity of heart failure, the overall condition of the heart and the response of the heart to various medical interventions in the treatment of heart failure.

The CardioMEMS™ heart failure monitoring device has been shown to significantly reduce heart failure related hospital admissions by 43%, reduce heart failure related mortality by 57%, and improve the quality of life in NYHA class III heart failure patients. The CardioMEMS™ HF System uses a miniaturized, wireless monitoring sensor implanted in a basilar segmental pulmonary artery branch via a transcatheter approach following femoral venipuncture. The internal sensor is paired with an external electronic device that allows patients to transmit their individual pulmonary artery pressure data from home directly to their cardiologists for personalized heart failure treatment and augmentation in therapy. The permanently implanted pulmonary artery sensor contains no batteries, leads or wires, is about the?size of a dime, and has two thin loops at each end. The sensor will not interfere with other devices such as a pacemaker or defibrillator. The CardioMEMS™ HF System is contraindicated in patients that cannot take dual antiplatelet or anticoagulants for at least one month following the implantation. Other relative contraindications are listed in Table 1 below:

 

 

 

Table 1. Relative Contraindications to CardioMEMS™ HF System Deployment

Active Infection

Recurrent (> 1) Pulmonary Embolism (PE) or Deep Venous Thrombosis (DVT)

 

Unable to Tolerate Right Heart Catheterization

Glomerular Filtration Rate (GFR) <25 ml/min (non-responsive to diuretic therapy or receiving chronic renal dialysis

Pre-existing Congenital Heart Disease or Mechanical Right Heart Valve(s)

Hypersensitivity or Allergy to Aspirin and/or Plavix (Clopidogrel)

Recent Implantation of a Cardiac Resynchronization Device (CRT) (< 3 months)

BMI > 35

 

The CardioMEMS™ HF System is deemed to be MRI Conditional. That is, patients with this device can be safely scanned immediately after implantation in a static magnetic field of 1.5 or 3.0 Tesla.

 

Selected Readings

1.     https://www.google.ca/#q=cardiomems+procedure

2.     http://professional.sjm.com/therapies/cardiomems/isw

3.     Abraham, W. T., et al. Pulmonary artery pressure management in heart failure patients with reduced ejection fraction significantly reduces heart failure hospitalizations and mortality above and beyond background guideline-directed medical therapy. Abstract 902-04 presented at ACC 2015, San Diego, CA. *Defined as the inability to obtain readings.

4.     Adamson, PB. AHA 2014 Session AOS.506.02. Heart Failure: Readmission, Quality of Care and the Cure? Impact of Wireless Pulmonary Artery Pressure Monitoring on Heart Failure Hospitalizations and All-Cause 30-Day Readmissions in Medicare-Eligible Patients With NYHA Class III Heart Failure: Results From the CHAMPION Trial Abstract 16744. http://www.abstractsonline.com/pp8/#!/3547/presentation/42447

5. Abraham WT, CHAMPION Trial Study Group, et al. Wireless pulmonary artery hemodynamic monitoring in chronic heart failure: a randomized controlled trial. Lancet. 2011. http://dx.doi.org/10.1016/S0140-6736 (11) 60101-3.

Correct answers by users

Radiology Medicine/Pulmonary
VCU Resident
  • Chris Goodman
    Others
    VCU Department of Thoracic Imaging Virginia Commonwealth University VCU Medical Center