Division of Cardiology
Carlos Morillo
MD, FRCP(C), FACC
Research Interests
- Sympathetic Microneurography
- Baroreflex modulation
- Heart rate and blood pressure variability
- Linear and non-linear dynamics of biological signals
- Plethysmography
- Lower body negative pressure
- Tilt table testing
The primary focus of my work is the understanding of the physiologic mechanisms that control blood pressure and heart rate during different physiologic and non-physiologic stimuli in humans. I have a particular interest in baroreflex control both at the vagal and sympathetic levels and their role during different situations such as vasovagal syncope, supraventricular and ventricular tachycardias. I also have a great interest in the role of cardiovascular reflex responses and their prognostic value in coronary artery disease, sudden cardiac death and stroke.
Specific studies include:
- Investigation of cardiovascular autonomic control during orthostatic stress in subjects with recurrent vasovagal syncope.
- Determine the role of cardiac resynchronization therapy and restoration of cardiac and vascular reflexes.
- Determine the prognostic value of baroreflex sensitivity, heart turbulence and T wave alternans in patients at risk of sudden cardiac death.
- The effects of simulated ventricular tachycardia on sympathetic and vagal baroreflex mechanisms.
- Investigation of the normal baroreflex and vascular response to orthostatic stress in male and female and in different age groups.
Selected Publications
- Taylor JA, Morillo CA, Ellenbogen KA, Eckberg DL. (1996) Higher sympathetic nerve activity during ventricular (VVI) than during Dual-chamber (DDD). J Am Coll Cadiol 28:1753-1758.
- Ellenbogen KA, Morillo CA, Wood MA, Gilligan DM, Eckberg DL, Smith ML. (1997) Neural monitoring of vasovagal syncope. PACE 20:788-794.
- Morillo CA, Jones DL, Klein GJ. (1996) Effects of autonomic manipulation on ventricular fibrillation and internal cardiac defibrillation thresholds in pigs. PACE 19:1355-1362.
- Morillo CA, Eckberg DL, Ellenbogen KA, Beightol L, Hoag JB, Tahvanainen KUO, Kuusela TA, Diedrich AM. (1997) Vagal and sympathetic mechanisms in patients with orthostatic vasovagal syncope. Circulation 96:2509-2513.
- Morillo CA, Camacho ME, Wood MA, Gilligan DM, Ellenbogen KA. (1999) Diagnostic utility of mechanical, pharmacologic and orthostatic stimulation of the carotid sinus in patients with unexplained syncope. J Am Coll Cardiol 34:1587-1594.
- Yoon BW, Morillo CA, Cechetto D, Hachinski V. (1997) Cerebral hemispheric lateralization in cardiac autonomic control. Archives of Neurology 54;741-744.
- Rudas L, Crossman A, Morillo CA, Halliwill JR, Tahvanainen KUO, Kuusela TA, Eckberg DL. (1999) Human sympathetic and vagal baroreflex responses to sequential nitroprusside and phenylephrine. Am J Physiol (Heart Circ Physiol) 276:H1691-H1698.
- Villar JC, Leon H, Morillo CA. (2004) Cardiovascular autonomic testing in asymptomatic T. Cruzi carriers: A sensitive method for clinical staging of Chagas’ disease. Int J Cardiol 93:189-195.
- Leon H, Guzman JC, Kuusela T, Dillenburg R, Kamath M, Morillo CA. (2005) Impaired baroreflex gain in patients with inappropriate sinus tachycardia. J Cardiovasc Electrophysiol 16(1):64-8.


