Case-of-the-Week

Case of the Week

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AMA Category 1 Credit for Physicians Only.
ASRT CME is not available.

Case-of-the-Week Information

The Case-of-the-Week is a presentation of 8 or more video loops to present an important topic in echocardiography. Please reveiw the image or video loops and then answer the questions below. After you have answered the questions you can view the explanation and obtain CME credit (if available).

You can change the size and the format of the image or video loops by using the links below the image or video loop.

= Windows Media Video	= MP4 Video
= QuickTime	= WebM Video
= Flash	= Ogg Video
= JPG Image	= GIF Image
Video Sizes
1X = 200x150 pixels 2X = 400x300 pixels	3X = 600x450 pixels 4X = 800x600 pixels

Loop Text Key
Preop	Preop TEE or TTE
Intraop	An Intraop TEE
IntraopPreOp	Intraop TEE or TTE before Operation
IntraopPostOp	Intraop TEE or TTE after Operation
IntraopEnd	Intraop TEE or TTE at End of Anesthesia
Post Op	Postop TEE or TTE

Case of the Month Information Table

IntraopEnd is usually a TEE after the Operation and after some event occured to show a change in the TEE

Complex Multiple Valvular Case

Case#: 25

AMA CME Units: 0.25 Units
Estimated Time: 15 minutes. You need more cme units to do this COTW for CME (not required). Purchase CME Credits

Presentation:
37 yo female with SOB, DOE, edema and a history of RF.

What is the presenting diagnosis and recommended therapy?
Any new diagnoses after operative therapy?
What are the indications of Bi-Ventricular pacing?
What are the advantages of Bi-Ventricular pacing?
Explain the electrical connections in Bi-Ventricular Pacing in the OR?

Loops:

Case Discussion/CME Questions

The echo exam shows spontaneous echo contrast in the LA and a hockey-stick formation and hypomobility of the mitral valve. The mitral valve is thickened. The LAA is without thrombus. The left and right atrium are enlarged. The mitral valve has a PISA formation. The PHT of the MV is 318-164 msec for a MVA of 0.60 - 0.68 cm².

The left atrial appendage peak velocity is 0.28 m/sec.

The aortic vale is hypomobile, thickened, and shows fibrosis at the commissures. The CFD shows severe AR with a wide jet that extends into the apex of the LV. The PISA formation of the AV during diastole has a radius of 0.79 cm (although this looks larger than that to me :). The LOVTd is 2.22 cm. The AV has stenosis but no Doppler studies are available to assess the severity.

The tricuspid valve has severe MR by jet area on CFD and by hepatic vein Doppler. The IVC is enlarged.

The anterior and inferior walls have normal motion. The septal wall exhibits a septal bounce at the beginning of diastole - presumably from the severe AR.

The patient has severe aortic regurgitation, severe tricuspid regurgitation, aortic stenosis of unknown severity and severe mitral stenosis from rheumatic heart disease. The pulmonary valve was spared.

The recommended therapy is MV and AV replacement and TV annuloplasty.

After the operative therapy the valves were interrogated. The TV had a very small gradient. The MV peak gradient was 9 mmHg which should put the mean gradient around 5-6 mmHg. The AV peak gradient was in the low 20's mmHg.

Also after the operative therapy a new onset LBBB was present that simulated an anterior wall motion abnormality.

Biventricular pacing is indicated in heart failure. In the operating room it is indicated for patients with a wide-QRS with hypotension due to cardiac dissynchrony. The specific indication according to the ACC/AHA/HRS 2008 pacing guidelines are:

Class I

1 For patients who have LVEF less than or equal to 35%, a QRSduration greater than or equal to 0.12 seconds, and sinus rhythm,CRT with or without an ICD is indicated for the treatment ofNYHA functional Class III or ambulatory Class IV heart failuresymptoms with optimal recommended medical therapy. (Level ofEvidence: A) (222,224,225,231)

Class IIa

1 For patients who have LVEF less than or equal to 35%, a QRSduration greater than or equal to 0.12 seconds, and AF, CRTwith or without an ICD is reasonable for the treatment of NYHAfunctional Class III or ambulatory Class IV heart failure symptomson optimal recommended medical therapy. (Level of Evidence:B) (220,231)

2 For patients with LVEF less than or equal to35% with NYHAfunctional Class III or ambulatory Class IV symptomswho arereceiving optimal recommended medical therapy and whohave frequentdependence on ventricular pacing, CRT is reasonable.(Levelof Evidence: C) (231)

Class IIb

1 For patients with LVEF less than or equal to 35% with NYHAfunctional Class I or II symptoms who are receiving optimalrecommended medical therapy and who are undergoing implantationof a permanent pacemaker and/or ICD with anticipated frequentventricular pacing, CRT may be considered. (Level of Evidence:C) (231)

Class III

1 CRT is not indicated for asymptomatic patients with reducedLVEF in the absence of other indications for pacing. (Levelof Evidence: B) (222,224,225,231)

2 CRT is not indicated forpatients whose functional statusand life expectancy are limitedpredominantly by chronic noncardiacconditions. (Level of Evidence:C) (231)

Biventricular pacing is indicated if the LVEF is less than 35% or a QRS that is wider than 0.12 msec and cardiac failure is present despite optimal medical therapy as a Class I/Evidence A recommendation.

Wang showd an increase in cardiac output of 10% when Bi-V pacing was initiated. Dzemali showed that 59% of patients responded to Bi-V pacing with improved hemodynamics. 40% did not show any improvement.

Luzi tried different locations on the RV to find the best site for BiV pacing. The sites were the interventricular septum, the pulmonary trunk, the AV junction and the acute margin. The best site that provided optimal BiV pacing was the interventricular septum.

Other authors showed that biventricular pacing did not improve the hemodynamics of the patient. It appears that about 30% of patients will not respond to BiV pacing. Using the newer 3D TEE machines you can view the septal to lateral delay before and after BiV pacing and optimize the delay in the operating room.

The advantages of biventricular pacing are to:

Decreased Systolic Time -> Increased Diastolic Filling Time
Improved Stroke Volume/Ejection Fraction
Earlier Closure of the Mitral valve

The MUSTIC and MIRACLE trials showed hemodynamic improvement in patients with heart failure who underwent biventricular pacing. Ventricular remodeling can also occur. The mitral regurgitation that was present had decreased.

Biventricular pacing requires 2 dipoles (one lead on the heart and one lead for a ground) that are 180 degrees apart in the heart. Therefore, you should have 4 wires - two attached to the heart 180 degrees apart and a ground for each cardiac lead. Usually, the atrium is paced also. To pace the atria a similar arrangement should be present. The inferoseptal wall and anterolateral wall or the anteroseptal wall and inferolateral wall are 180 degrees apart.

Please answer the following questions correctly to obtain your CME.

Web Links/References

ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities
Optimized temporary biventricular pacing acutely improves intraoperative cardiac output after weaning from cardiopulmonary bypass: A substudy of a randomized clinical trial
Optimized perioperative biventricular pacing in setting of right heart failure.
The effect of biventricular pacing after coronary artery bypass grafting: A prospective randomized trial of different pacing modes in patients with reduced left ventricular function
Best Site on Right Ventricle for Open-Chest Biventricular Pacing
Intraoperative Biventricular Pacing - PCCVS
Benefit of cardiac resynchronization in elderly patients: results from the Multicenter InSync Randomized Clinical Evaluation (MIRACLE) and Multicenter InSync ICD Randomized Clinical Evaluation (MIRACLE-ICD) trials.
Long-term benefits of biventricular pacing in congestive heart failure: results from the MUltisite STimulation in cardiomyopathy (MUSTIC) study.