Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Oct 30;60(18):1764-75.
doi: 10.1016/j.jacc.2012.07.052. Epub 2012 Oct 3.

Development of a novel echocardiography ramp test for speed optimization and diagnosis of device thrombosis in continuous-flow left ventricular assist devices: the Columbia ramp study

Nir Uriel  1 , Kerry A Morrison, Arthur R Garan, Tomoko S Kato, Melana Yuzefpolskaya, Farhana Latif, Susan W Restaino, Donna M Mancini, Margaret Flannery, Hiroo Takayama, Ranjit John, Paolo C Colombo, Yoshifumi Naka, Ulrich P Jorde
Affiliations

Development of a novel echocardiography ramp test for speed optimization and diagnosis of device thrombosis in continuous-flow left ventricular assist devices: the Columbia ramp study

Nir Uriel et al. J Am Coll Cardiol. .

Abstract

Objectives: This study sought to develop a novel approach to optimizing continuous-flow left ventricular assist device (CF-LVAD) function and diagnosing device malfunctions.

Background: In CF-LVAD patients, the dynamic interaction of device speed, left and right ventricular decompression, and valve function can be assessed during an echocardiography-monitored speed ramp test.

Methods: We devised a unique ramp test protocol to be routinely used at the time of discharge for speed optimization and/or if device malfunction was suspected. The patient's left ventricular end-diastolic dimension, frequency of aortic valve opening, valvular insufficiency, blood pressure, and CF-LVAD parameters were recorded in increments of 400 rpm from 8,000 rpm to 12,000 rpm. The results of the speed designations were plotted, and linear function slopes for left ventricular end-diastolic dimension, pulsatility index, and power were calculated.

Results: Fifty-two ramp tests for 39 patients were prospectively collected and analyzed. Twenty-eight ramp tests were performed for speed optimization, and speed was changed in 17 (61%) with a mean absolute value adjustment of 424 ± 211 rpm. Seventeen patients had ramp tests performed for suspected device thrombosis, and 10 tests were suspicious for device thrombosis; these patients were then treated with intensified anticoagulation and/or device exchange/emergent transplantation. Device thrombosis was confirmed in 8 of 10 cases at the time of emergent device exchange or transplantation. All patients with device thrombosis, but none of the remaining patients had a left ventricular end-diastolic dimension slope >-0.16.

Conclusions: Ramp tests facilitate optimal speed changes and device malfunction detection and may be used to monitor the effects of therapeutic interventions and need for surgical intervention in CF-LVAD patients.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Consideration for the Ramp Test Algorithm Algorithm for consideration of ramp studies based on anticoagulation studies and presence of intracardiac thrombus.
Figure 2
Figure 2
Images for Obtaining TTE Parameters 2a: LVEDD assessment in the parasternal long axis view. 2b: Aortic valve opening assessment by M-mode. 2c: Aortic valve insufficiency assessment by color Doppler. 2d: Mitral valve insufficiency assessment by color Doppler. 2e: Right ventricular systolic pressure assessment by Doppler.
Figure 2
Figure 2
Images for Obtaining TTE Parameters 2a: LVEDD assessment in the parasternal long axis view. 2b: Aortic valve opening assessment by M-mode. 2c: Aortic valve insufficiency assessment by color Doppler. 2d: Mitral valve insufficiency assessment by color Doppler. 2e: Right ventricular systolic pressure assessment by Doppler.
Figure 2
Figure 2
Images for Obtaining TTE Parameters 2a: LVEDD assessment in the parasternal long axis view. 2b: Aortic valve opening assessment by M-mode. 2c: Aortic valve insufficiency assessment by color Doppler. 2d: Mitral valve insufficiency assessment by color Doppler. 2e: Right ventricular systolic pressure assessment by Doppler.
Figure 2
Figure 2
Images for Obtaining TTE Parameters 2a: LVEDD assessment in the parasternal long axis view. 2b: Aortic valve opening assessment by M-mode. 2c: Aortic valve insufficiency assessment by color Doppler. 2d: Mitral valve insufficiency assessment by color Doppler. 2e: Right ventricular systolic pressure assessment by Doppler.
Figure 2
Figure 2
Images for Obtaining TTE Parameters 2a: LVEDD assessment in the parasternal long axis view. 2b: Aortic valve opening assessment by M-mode. 2c: Aortic valve insufficiency assessment by color Doppler. 2d: Mitral valve insufficiency assessment by color Doppler. 2e: Right ventricular systolic pressure assessment by Doppler.
Figure 3
Figure 3
Normal Example vs. Device Thrombosis Example of LVEDD, PI, and Power Graphs 3a: LVEDD slope, PI slope, and power slope of a patient with normal device function. 3b: LVEDD slope, PI slope, and power slope of a patient with device thrombosis
Figure 3
Figure 3
Normal Example vs. Device Thrombosis Example of LVEDD, PI, and Power Graphs 3a: LVEDD slope, PI slope, and power slope of a patient with normal device function. 3b: LVEDD slope, PI slope, and power slope of a patient with device thrombosis
Figure 4
Figure 4
Histograms of LVEDD, LDH, AV Closure Speeds, PI, and Power Slopes
Figure 4
Figure 4
Histograms of LVEDD, LDH, AV Closure Speeds, PI, and Power Slopes
Figure 4
Figure 4
Histograms of LVEDD, LDH, AV Closure Speeds, PI, and Power Slopes
Figure 5
Figure 5
Photo of Confirmed Device Thrombosis upon Explant
Figure 6
Figure 6
Roc Curve Analysis of LDH as Indicator of Device Thrombosis The specificity and sensitivity values for LDH as an indicator for thrombosis were identified from the ROC curve. An LDH value above 750 u/mL has a specificity of 85% and should trigger further evaluation for device thrombosis diagnosis. The optimal results were achieved with an LDH cutoff of 1103 u/mL. The blue region of the graph represents a 95% confidence interval for the ROC curve using the bootstrap method in the pROC package in R version 2.15.0.
Figure 7
Figure 7
Suspected Device Malfunction Algorithm Suggested management algorithm for patients with suspected device thrombosis.
See this image and copyright information in PMC

Comment in

References

    1. Slaughter MS, Rogers JG, Milano CA, et al. Advanced heart failure treated with continuous-flow left ventricular assist device. N Engl J Med. 2009 Dec 3;361(23):2241–2251. - PubMed
    1. Miller LW, Pagani FD, Russell SD, et al. Use of a continuous-flow device in patients awaiting heart transplantation. N Engl J Med. 2007 Aug 30;357(9):885–896. - PubMed
    1. Pagani FD, Miller LW, Russell SD, et al. Extended mechanical circulatory support with a continuous-flow rotary left ventricular assist device. J Am Coll Cardiol. 2009 Jul 21;54(4):312–321. - PubMed
    1. John R, Naka Y, Smedira NG, et al. Continuous flow left ventricular assist device outcomes in commercial use compared with the prior clinical trial. Ann Thorac Surg. Oct;92(4):1406–1413. discussion 1413. - PubMed
    1. Park SJ, Milano CA, Tatooles AJ, et al. Outcomes in advanced heart failure patients with left ventricular assist devices for destination therapy. Circ Heart Fail. Mar 1;5(2):241–248. - PubMed

Publication types