I Had an 80% Coronary Blockage at 44. Every Test Said I Was Fine.

A little over a year ago I was driving home from Mayo Clinic after getting a coronary CT angiogram (CCTA). A CCTA is a specialized CT scan that uses contrast dye to look directly at the arteries feeding your heart. I had gone through three weeks of previous tests (all normal) and had to argue with my cardiologist to get it. It picks up both the hard, calcified plaque and the soft plaque that can rupture without warning and kill you. Working in the emergency department at Mayo Clinic, I unfortunately see the end result of plaque ruptures on a frequent basis.

While merging onto a busy interstate, I got a notification on my phone. The first line read: “Critical result: severe, flow-limiting occlusion of the right coronary artery.”

I pulled the car over in a state of shock. I knew exactly what those words meant. From helping run codes on a daily basis in ER, I just discovered I could be on the receiving end at any moment.

My name is Nick Hanson. I’m a former health and wellness industry CEO turned clinician-scientist. I’ve been from the boardroom, to the bench, to the bedside. This is the story of how I ended up with a chunk of metal in my coronary artery, why I’m angry about it, and why I started Calibrated Signal.

I was 44 years old. Former athlete, lifelong exerciser, non-smoker, non-drinker. I had a master’s in bioinformatics from a joint program between the University of Minnesota, Mayo Clinic, IBM, and Cray Computers. I had published cancer epigenetics research. I’d spent 15 years as a health and wellness industry CEO. I had a curated and optimized multi-supplement stack, a sauna, an ice bath, and a low-carb high-fat diet that the biohacking world swore was optimal.

None of it mattered. I had an 80% coronary blockage and was one bad day away from a heart attack that could have killed me. I just discovered I was a literal ticking time bomb. My first emotion? Pure anger as I thought I was doing everything right.

The Diagnostic Fight

A month before that scan, I was sitting across from my Mayo Clinic cardiologist with a complaint of vague chest tightness. It would come on without warning, not necessarily tied to exercise. Sometimes it actually got better when I worked out. I had a history of mild anxiety and some disc degeneration in my spine, so I acknowledged it could be either of those. But it had been getting worse over the past few months, and something felt off.

We ran everything. A comprehensive lab panel came back mostly normal. My hsCRP, a marker for chronic inflammation, was rock bottom at 0.45. Homocysteine normal. HbA1c looked great, no insulin resistance. I wore a continuous glucose monitor for a few weeks with zero concern. No issues with Lp(a) (a common culprit for atherosclerosis that is primarily determined through genetics). The only flag was my LDL (low-density lipoprotein, the cholesterol particle most tied to artery plaque) at 160, moderately elevated and slightly higher than it had trended most of my adult life. But many of the popular biohacking physicians and low-carb/high fat keto and carnivore advocates said mildly high LDL was of little concern in the absence of insulin resistance or chronic inflammation. I had neither.

My 12-lead ECG also came back normal sinus rhythm. I run these all day in the ER. It looked perfect.

He asked about wearable data as he could see the Apple Watch on my wrist and Oura Ring on my finger, neither of which had ever flagged high heart rates and showed excellent resting heart rate in the low 50s. The cardiologist seemed reassured.

I pushed back. I wanted to go deeper.

He was hesitant. Eight years earlier, at 36, I’d had a complete cardiac workup that included a 100% clean CCTA, one that found zero calcified or non-calcified plaque. With that history, and everything in front of him now reading normal, he saw little reason to keep digging. He did agree to add a Holter monitor to track my heart rhythm for a couple of days, something I hadn’t needed in 2016, because I’d started having some palpitations.

The Holter came back normal too. Zero concerns. (Here’s why those tests missed my 80% blockage.)

At follow-up he told me I could chalk this up to referred pain from my spinal disc issues triggering low-level anxiety. He pointed out that sometimes in the medical profession, when you know too much, your mind can run. I could see his point. I deal with heart attacks every day in the ER. It’s easy to let your mind go down that path.

But I had this gnawing feeling that something wasn’t right. I didn’t have the same pep in my workouts. I was getting tired sooner than normal. So I basically begged him to order a CCTA so I could eliminate my “heart attack anxiety” once and for all. If that came back clean, I’d stop chasing tests.

He was reluctant. A clean CCTA eight years ago made it hard to justify. But my LDL had been creeping up since I’d changed my diet, and he wasn’t a fan of the high-fat approach to begin with. He agreed. I agreed to reconsider a statin depending on the result.

The Result

A severe occlusion of my right coronary artery was not the result either of us expected. Mild atherosclerosis was also discovered in my left main and left coronary arteries. The right was labeled severe and flow-limiting. My heart was being starved of blood, and I was a walking time bomb that hadn’t detonated yet.

Within days I was scheduled for a stent with one of Mayo’s top interventional cardiologists. The procedure went as planned. Afterward, the interventionist handed me before-and-after images and told me that only a few blood cells at a time could squeeze past the occlusion.

That was all that was keeping the rest of my heart alive. He said I was one bad day away from a heart attack that could have been deadly.

The Reckoning

I spent the next month in a strange state of relief and anger. Relief that I wasn’t crazy. Relief that I’d fought for the test. Anger that I thought I was doing everything right.

Here’s the part that keeps me up at night. I didn’t stumble onto a ketogenic diet from some Instagram influencer. I found it while researching the Warburg effect and mitochondrial theory of cancer during my time publishing epigenetics research.¹ The Warburg effect describes how cancer cells preferentially use glucose for energy even when oxygen is available.² It’s a real metabolic phenomenon, and the hypothesis that restricting glucose could starve cancer cells had legitimate scientific interest behind it. I became a proponent of low-carb approaches based on what I thought the metabolic science supported.

Turns out the science I trusted didn’t account for what was happening inside my coronary arteries.

By every metric the keto and carnivore community uses to dismiss LDL concerns, I should have been fine. Rock-bottom inflammation. No insulin resistance. Perfect metabolic markers. The biggest thing I had changed was my diet. I had adopted a high-fat ketogenic and, at times, carnivore approach, and my LDL had quietly climbed during that period. I’m not pretending that one dietary change explains the entire biology of an 80% RCA occlusion. But it was the signal I had been taught to downplay, and it is the signal I now wish I had taken more seriously. The damage had been accumulating inside arteries that only the test I argued for could see.

Had I not been a published scientist and ER nurse who knows how to talk to doctors, I would not have gotten that scan. That blockage would still be there, or it would be decaying along with my body in a cemetery somewhere. That’s not dramatic. That’s the math.

If someone with my training could barely argue for the right diagnostic, what chance does someone have who doesn’t know the words to use?

The Connection I Didn’t See Coming

Before the cardiac event, before the ER, I spent three years at the Hormel Institute, a cancer research center run jointly by the University of Minnesota and Mayo Clinic. I worked in a cell signaling lab focused on epigenetic mechanisms of drug resistance in melanoma. My research centered on H3K27, a histone marker involved in how cancer cells evade treatment.

I didn’t choose that research topic. You don’t get to pick your PI’s focus when you’re a grad student. I spent years learning that particular piece of molecular machinery without any idea where it would lead.

H3K27 turned out to be tied to the same machinery behind modern biological aging clocks. Those clocks, the ones researchers like Steve Horvath built to measure how fast humans age, read DNA methylation. And the regions they watch most closely are the very ones kept silent by H3K27, the mark I’d spent years studying. I had no way of knowing that at the time. Nobody in my lab was thinking about aging. We were thinking about melanoma and brain cancer.

That connection, the realization that my cancer research mapped directly onto the longevity science I’d end up writing about, wasn’t planned or engineered. It was uncanny, accidental, and it changed how I understood my own career. The boardroom taught me how health products are marketed. The bench taught me how biology actually works at the molecular level. The bedside taught me what happens when patients don’t have the information they need. And a stent at 44 taught me that even someone with all three of those perspectives can still get it wrong.

That is why this site does not stop at cholesterol, scans, or stents. My heart was the event that forced the question, but the deeper question is biological aging.

What Calibrated Signal Is

After the stent, I decided to apply the same evidence-based lens I learned in cancer research to every aspect of my health. Calibrate every claim against the real data. Keep the signal. Throw out the noise, no matter how popular it is or who’s promoting it. That’s where the name comes from.

I read the full papers. Not abstracts, not summaries of summaries. The methods sections, the results tables, the supplementary data most people never open. My bioinformatics training means I can evaluate study design and statistics at a level most content creators skip entirely. My 15 years inside the supplement industry means I know which claims are evidence and which are marketing dressed up as science. I’ve formulated the products, managed the manufacturing, negotiated with the raw material suppliers. I know what’s in most bottles and what isn’t.

When the evidence supports something, I’ll tell you clearly. When it doesn’t, I’ll tell you that too. When we don’t know yet, I’ll say so. I would rather be honest than comfortable.

I don’t take sponsors. I don’t accept money to feature products. When I link to something, I’ll disclose the relationship, compare it to the alternatives, and let you decide. The information here is free and always will be.

Everyone deserves the same information I had when I argued for the test that saved my life. That’s it. That’s the mission.

What’s Next

Next week I’m going to tear apart the study that the keto and carnivore community points to when they tell you elevated LDL doesn’t matter if your metabolic markers are clean. I believed that study. I built my diet around it. And while my coronary artery was quietly closing, every biomarker it told me to watch said I was fine.

That post is personal. This one was the story. That one is the science.

If you haven’t signed up for the newsletter yet, do it here so you don’t miss it. And if you know someone who’s been told their LDL is “nothing to worry about” because their inflammation markers are low, send them this post.

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References

¹ Grigore F, Yang H, Hanson ND, et al. “BRAF inhibition in melanoma is associated with the dysregulation of histone methylation and histone methyltransferases.” Neoplasia. 2020;22(9):376-389. PMID: 32629178 · doi:10.1016/j.neo.2020.06.006

² Seyfried TN, Shelton LM. “Cancer as a metabolic disease.” Nutrition & Metabolism. 2010;7:7. PMID: 20181022 · doi:10.1186/1743-7075-7-7