Reviewed by R. Theodore Smith, MD, PhD
R. Theodore Smith, MD, PhD, Professor of Ophthalmology at the Icahn School of Medicine at Mount Sinai, New York, reported that cardiac arrhythmias such as atrial fibrillation are associated with subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD). The SDDs may serve as a biomarker of serious heart disease. He presented his results at the 2024 American Academy of Ophthalmology annual meeting, Chicago.
Two forms of AMD that are high risk for late AMD, are drusen under the retinal pigment epithelium (RPE) and SDDs above the RPE with choroidal thinning. Besides location, they differ markedly in genetic risks, cholesterols, prognosis for late AMD, and death, with the last 2 occurring sooner in association with SDDs.1
“We had long known that SDDs were associated with earlier death,” Dr. Smith explained.1 “Now we know why.”
Dr. Smith’s team has recently reported that other high risk (for death) vascular diseases (HRVDs) such as myocardial infarction, cardiac valve disease, and ischemic stroke are strongly associated with AMD and SDDs , not drusen (p = 0.000000009).2 “For patients, SDDs are a warning they may face an early death from these diseases: cardiac type I, myocardial; cardiac type II, valvular; and neurovascular, ischemic stroke,” Dr. Smith said. “Medical attention is indicated.” The next logical step was to look at arrhythmias.
In type I and type II cardiac HRVDS, heart disease causes low flow to the entire body, including low choroidal blood flow, with photoreceptor hypoxic damage, and SDDs. Ischemic stroke is caused by carotid artery disease which in turn causes low choroidal flow to the ipsilateral eye, and SDDs. We now have type III cardiac HRVDS, the arrhythmias like atrial fibrillation and atrial flutter. These cause irregular ventricular filling and poor systemic perfusion, resulting likewise in poor ocular perfusion downstream and SDDs.3
In their arrhythmia study, Dr. Smith and colleagues investigated 71 patients with cardiac disease and arrhythmias and no retinal disease.
He reported that 43% of cardiac subjects with arrhythmias had SDDs, which exceeds the percentage (23%) reported in an older population.4 This occurs because mean cardiac index is below normal in arrhythmias, 1.95 vs. 2.71 L/min/m2 , thus causing poor ocular perfusion and SDDs, he explained.
The investigators reached the following conclusions.