• Research & Clinical Studies

    Cardiac Stress Testing with Transesophageal Atrial Pacing for Diagnosis of Coronary Artery Disease and Myocardial Ischemia

    "Bedside pacing stress echocardiography is feasible and safe, and highly correlates with myocardial perfusion stress scintigraphy for identifying inducible myocardial ischemia in patients with new onset of chest pain or unstable angina." Atar S, Siegel RJ, et al. Am J Cardiol 86(1):12-16, 2000. Abstract

    "Echocardiography with transesophageal atrial pacing appears to be the most economical procedure, scintigraphy the least, while dobutamine stress echo testing falls somewhere in between." Don Michael TA, et al. Am J Cardiol 75: 563-567,1995. Abstract

    "Transesophageal pacing with transesophageal echocardiography performed in our patients with sinus rhythm was effective, short-lasting, well tolerated, complication free, immediately repeatable, reversible, and capable of being performed as an outpatient procedure."
    Don Michael TA, et al. Am J Cardiol 77:187-190, 1996. Abstract

    "Transesophageal atrial pacing is safe and well tolerated. The principle advantages of TAP (as compared to Dobutamine stress) are reduced time and effort of the procedure." Pellikka P, Lee CY, Stewart JB. Circulation Suppl. #96, Abstr 196,1997. Abstract

    Mayo Clinic Study #1 :   TAPtest TM vs. Dobutamine  

    Methods: 100 patients were administered stress echo tests using both TAPtest (CardioCommand, Inc) and Dobutamine (standard Mayo protocol). Esophageal pacing rate was incremented by 20 BPM every 2 mins until target HR attained.
    Results:   TAPtest  


      duration of procedure (min)  9.6 29
      achieved target HR 98% 89%
      dysrhythmias  1%  13%
      wall motion concordance good -----

    Conclusions: As compared to Dobutamine, TAPtest
    • is comparable for the diagnosis of ischemic disease,
    • is safe and well tolerated by patients,
    • yields more reliable capture of target heart rate,
    • has lower incidence of dysrhythmias,
    • reduces echocardiography procedure time by 20 mins.

    From: Nonexercise stress transthoracic echocardiography: transesophageal atrial pacing versus dobutamine stress. Lee CY, Pellikka PA, McCully RB, Mahoney DW, Seward JB. Div of Cardiovascular Diseases and Internal Medicine, Mayo Clinic. J Am Coll Cardiol 33(2):506-11, 1999.

    Mayo Clinic Study #2 :   TAPtest TM vs. Dobutamine  

    Methods: 35 patients were administered stress echo tests using both TAPtest (CardioCommand, Inc) and Dobutamine (standard Mayo protocol). Esophageal pacing was performed at 85% and 100% of target HR (rapid stress protocol).
    Results:   TAPtest  


      Heart rate at peak stress (beats/min) 144 123
      Ischemic segments detected (%) 62 42
      Time to perform/review test (min)  30 44
      Patient acceptance score (5 = high) 4.2 3.8

    Conclusions: As compared to Dobutamine, the rapid 2-stage TAPtest
    • is well accepted by patients,
    • induces higher peak heart rates and greater myocardial ischemia,
    • reduces time to perform and review echocardiography exams.

    From: A New Rapid Stress Testing Protocol: Comparison of Two-Stage Transesophageal Atrial Pacing Stress Echocardiography with Dobutamine Stress Echocardiography. Rainbird AJ, Pellikka PA, Stussy VL, Mahoney DW, Seward JB Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic and Mayo Foundation. Abstract presented at American Society of Echocardiography, Washington DC. Jun, 1999.

    More Excerpts from the Experts on Echocardiagraphy &
    Cardiac Stress Testing with Transesophageal Atrial Pacing (TAP).

    Transesophageal Echo-Stress "appears a highly feasible and very safe test in the evaluation of patients with coronary artery disease. Its safety should be considered in comparison with pharmacological stressors, that have higher potential risk." Gallo A., Anselmi M., et al. #1530 Amer Heart Assoc, 1997. Abstract

    TAP "combined with simultaneous transesophageal echocardiography is a highly specific and sensitive technique for the detection of coronary artery disease. Ischemia-induced wall motion abnormalities were detected earlier than observed ECG changes. The technique appears to be particularly suited to patients who are unable to perform an active stress test or those with poor quality transthoracic echocardiograms." Lambertz H, Kreis A,et al. Amer Coll Cardiol 16(5):1143-1153,1990. Abstract

    "Sensitivity of remote asynergy during transesophageal atrial stimulation for detecting multivessel CAD was 82%, specificity 90%, and predictive accuracy 86%. TAP combined with 2-dimensional echocardiography can safely be performed in the early days of acute myocardial infarction; remote asynergy during TAP reliably identifies patients with multivessel disease and future ischemic events."  Res JC, Kamp O, et al. Am J Cardiol 76(16):1112-1114, 1995. Abstract

    "Transesophageal echocardiography during TAP is a feasible and promising alternative technique for the assessment of coronary artery disease, with a higher sensitivity than simultaneous 12-lead and exercise electrocardiography." Kamp O, De Cock C, et al. Am J Cardiol 1992;69:1412-1416 Abstract

    TAP "produced fewer false positive studies resulting in higher specificity compared to treadmill exercise. Some possible explanations of the improved specificity are the better quality tracings obtained with TAP and the increased control of the heart rate and blood pressure response during atrial pacing as opposed to treadmill exercise." Matthews RV, Haskell RJ, et al. J Electrocardiol 20 Suppl:157-62, 1987. Abstract

    TAP "combined with 2-dimensional echocardiography (echo-pacing) is useful for detecting the presence and site of jeopardized myocardium after an acute myocardial infarction." Anselmi M, Golia G, et al. Am J Cardiol 73(8):534-8, 1994. Abstract

    "TAP proves to be a valid and sensitive provocative test of ischemia when combined with myocardial scintigraphy". Santomauro M, et al. Angiology 43(10):818-25, 1992. Abstract

    With myocardial scintigraphy during treadmill exercise (TE) and transesophageal atrial pacing (TAP), "the predictive sensitivity for coronary stenosis was 83% for TE and 94% for TAP. The respective specificities were 71 and 78%. The comparison of segmental hypoperfusion after exercise and under TAP gave similar results in 230 of the 250 segments studied (92%). Thus, TAP provides an alternative diagnostic method to TE for the detection of coronary artery disease and can be performed in patients for whom the usual stress test is not possible, most particularly when dipyridamole is contraindicated because of a bronchospastic factor." Le Feuvre C, et al. Ann Med Interne (Paris) (France), 142(5) p325-9, 1991. Abstract