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The QT-Sensitive Cybernetic Pacemaker: A New Role for an Old Parameter?
PAOLO E. PUDDU,
JEAN TORRESANI,
PAOLO E. PUDDU
From II Cattedra di Cardiologia, University of La Sapienza, School of Medicine, Rome, Italy
Search for more papers by this authorCorresponding Author
JEAN TORRESANI
Service de Cardiologie, Hôpital Nord, University of Marseille, School of Medicine and INSERM U-175 (Experimental Cardiology), Marseille, France
Address for correspondence: Pr. Jean Torresani, INSERM U- 175, 18 Avenue Mozart, 13009 Marseille, France.Search for more papers by this authorPAOLO E. PUDDU,
JEAN TORRESANI,
PAOLO E. PUDDU
From II Cattedra di Cardiologia, University of La Sapienza, School of Medicine, Rome, Italy
Search for more papers by this authorCorresponding Author
JEAN TORRESANI
Service de Cardiologie, Hôpital Nord, University of Marseille, School of Medicine and INSERM U-175 (Experimental Cardiology), Marseille, France
Address for correspondence: Pr. Jean Torresani, INSERM U- 175, 18 Avenue Mozart, 13009 Marseille, France.Search for more papers by this authorDr. Puddu was supported by CIES contract numbers 30121-115-56548 (1978–79) and 31170-115-64598 (1981–83) and by INSERM-CNR contract number 08818 (1983–84). This work was also in part supported by CNR (Rome, Italy) contract number 8300-463-04 (1982–84).
Abstract
A critical review of the available data on QT interval is presented to delineate techniques useful to the development of a QT-sensitive cybernetic pacemaker. The reason for the development of this unit stems from the ability of QT prolongation to predict the onset of life-threatening ventricular arrhythmias in some clinical situations; the QT interval is physiologically related to the cardiac cycle length, therefore providing adequate information to drive both ventricuiar and atrioventricuiar sequential rate-responsive pacemakers. This unit might also monitor cardiac rhythm and detect the pathophysioiogic precursors of advanced grades of ventricular arrhythmias. A therapeutic role, both pharmacologic and electrical, may also be possible in the future. Integration of these concepts and cooperation between interested physicians, technicians and manufactors will be necessary to produce such a unit at a low cost-benefit ratio. The potential clinical application of this pacemaker deserves attention for the prophylaxis and treatment of sudden arrhythmic death.
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