Noradrenaline depletion in patients with coronary artery disease before and after percutaneous transluminal coronary angioplasty with iodine-123 metaiodobenzylguanidine and single-photon emission tomography

Abstract

Iodine-123 metaiodobenzylguanidine (MIBG) is a noradrenaline analogue which can be used as a tracer to investigate the cardiac sympathetic nervous system. Regional ischaemia leads to noradrenaline depletion with functional denervation which can be demonstrated by reduced MIBG uptake. In order to evaluate the reversibility of ischaemia-associated damage to the sympathetic nervous system, neuronal scintigraphy with 123I-MIBG and myocardial rest and stress perfusion scintigraphy with technetium-99m sestamibi was performed in 16 patients with coronary artery disease before and 3-4 months after percutaneous transluminal coronary angioplasty (PTCA). Partial re-innervation occurred in five patients, the degree of stenosis of remaining lesions being estimated by repeat angiography to be below 40%. Unchanged MIBG defects could be confirmed in four patients with residual lesions of between 40% and 50%. Increased MIBG defects were shown in three patients with significant restenoses of more than 70%. In all patients the neuronal defects exceeded the ischaemia-induced or scar-associated perfusion defects. Three patients dropped out of this study: one for technical reasons, one due to emergency aortocoronary bypass surgery and one due to diabetic polyneuropathy. This investigation shows that the sympathetic nervous system is highly sensitive to ischaemia. Further studies need to be done to assess the conditions allowing re-innervation after PTCA.

Stroke and Coronary Artery Disease Are Associated With Parkinson’s Disease

“…Cardiac sympathetic nerve is quite sensitive to ischemia. 29 Chronic cardiac sympathetic denervation might aggravate the cardiac ischemia by sustained elevation of end-diastolic pressure after ischemia. 30 In PD with orthostatic hypotension, chronic hypotension might result in exaggerated response to exogenously given adrenergic receptor agonists, a phenomenon called "denervation supersensitivity".…”

“…Another explanation for the relationship between CAD and PD is cardiac sympathetic denervation in PD. Cardiac sympathetic nerve is quite sensitive to ischemia 29 . Chronic cardiac sympathetic denervation might aggravate the cardiac ischemia by sustained elevation of end-diastolic pressure after ischemia 30 .…”

Untersuchungen des sympathischen Nervensystems bei stummer Ischämie mit 123J-Metajodbenzylguanidin (MIBG)

“…Myokardszintigraphisch gut perfundierte Myokardareale zeigten einen regelrechten 1 2 3 J-MIBG-Uptake. Insgesamt unterschieden sich die Befunde der regionalen Katecholamindepletion nicht von denen vergleichbarer KHK-Patienten mit schmerzhafter Ischämie (24), so daß eine globale, das gesamte Herz betreffende funktionelle oder strukturelle Denervierung als Ursache der stummen Ischämie ausge-schlössen werden kann. Experimentelle Untersuchungen an Hunden zeigten, daß die über sympathische Afferenzen und durch vagale Nerven evozierbaren Reflexe durch akut einsetzende Ischämien abgeschwächt wurden.…”

“…Unklar bleibt jedoch, weshalb sich dann Ischämien inter-und intraindividuell im Ausmaß des Schmerzes so stark unterscheiden. Die in dieser Studie festgestellten regionalen 1 2 3 J-MIBG-Defekte, die auf eine fehlende Neurotransmission im Bereich ischämischen und vernarbten Myokards mit apikaler und lateraler Denervierung hinwiesen, unterschieden sich nicht von dem Ausmaß der Katecholamindepletion symptomatischer Patienten, die wir vor und nach PTCA untersuchten (24). Interessanterweise war bei einem Teil dieser symptomatischen Patienten die Ischämieassoziierte sympathische Denervierung 3-4 Monate nach erfolgreicher PTCA mit Reststenosen, die weniger als 50% betrugen, partiell reversibel.…”

Transfer from PET to SPET in cardiology, but the unit of reference is still the patient

“…In all patients with coronary beast disease (CHD), the neuronal defects exceed the ischaemia-induced or scar-associated perfusion defects. Sympathetic denervation and re-innervation occur following acute myocardial infarction, and the denervated but viable myocardium can be detected non-invasively by combined 123I-mlBG and 2°1T1 SPET [16,25].…”