247 ‒ Preventing cardiovascular disease: the latest in imaging, blood pressure & metabolic health

KEYPOINTS

• 01

  A calcium scan is cheap and useful, but a zero doesn't rule out disease, especially in younger people.

  Weiss, a cardiologist who now volunteers as clinical faculty at UCSF after leaving his lab to start a biotech company, says he did 'a full 180' on CAC scans. They're low-risk, need no dye, and can cost about $200, though some places charge $2,000. His two-by-two: a zero in a 40-year-old with risk factors teaches little and shouldn't stop aggressive treatment, and a zero in a high-risk 80-year-old has its own false-negative problem. Attia cites data that about 15% of people with a zero score have something on CT angiography, and about 1.5–2% have an unstable plaque.

• 02

  CT angiography sees soft plaque and small calcium that CAC misses, at higher cost and some radiation.

  Attia says CTA often runs $700 to $2,000–2,500. Prices can differ tenfold between institutions, and fewer than half of Weiss's patients have coverage. A modern scan delivers about 2 mSv, roughly 4% of the annual allowance mentioned, but some older scanners use about 20 mSv. Attia advises shopping for both price and dose.

• 03

  Weiss treats causal risk factors, not end-stage findings.

  Waiting for 30% stenosis or a calcium score of 200 before acting is 'insane,' he says, comparing it to waiting for lung damage before telling someone to quit smoking. He describes 'eye-bleeding' fights with insurers who want a heart attack before approving PCSK9 inhibitors. With low enough apoB over a long enough runway, both argue, atherosclerosis could become largely irrelevant.

• 04

  For stable plaque, optimal medical therapy usually beats stenting.

  COURAGE, ISCHEMIA and ORBITA showed that optimal medical therapy works well even in mildly symptomatic patients. Clear stent cases are an active MI, rest or unstable symptoms, heart failure, or chest pain that doesn't respond to medicine. FAME and FAME 2 used fractional flow reserve (the pressure drop across a lesion) to show which lesions matter. Weiss notes that the plaques that rupture and cause sudden death are often smaller ones of about 30%, not 80–90% blockages.

• 05

  Statins can increase calcification while lowering events, so calcium isn't always a direct proxy for risk.

  Weiss calls it 'incontrovertible' that statins probably increase calcification even as they cut event risk, likely by stabilizing plaque. Whether heavy endurance exercise is similar is unknown. He wouldn't tell anyone not to exercise but is 'on the fence' about the most extreme volumes.

• 06

  Statin fear far exceeds actual statin harm.

  Weiss estimates that about 5% of patients have muscle side effects real enough to stop. A similar or larger group refuses statins out of fear fed by documentaries and online claims that they are 'poison,' even after 25–30 years of successful use. Liver enzyme rises also occur, especially combined with ezetimibe.

• 07

  Normal blood pressure is about 120/80 at any age, and drifting higher with age is disease.

  The old view allowed 'permissive hypertension' in older people. Weiss now tells patients the goal is to get as close to 120/80 as possible without side effects. He traces the definitions from JNC 6 to JNC 7, which called 120–140 'prehypertension,' and says the evidence, not opinion, now ties lower pressure to lower mortality.

• 08

  SPRINT showed a mortality benefit from intensive control, with manageable costs.

  The NIH-funded, drug-agnostic trial compared targets of about 120 against about 140 systolic and achieved roughly 121 versus 136. The results were strong enough that the trial was stopped early. Blood pressure was measured with automated cuffs, seated and alone, three readings five minutes apart. The intensive arm had more falls, syncope and kidney dysfunction, all reversible. STEP, published the year before this conversation, eased worries that SPRINT's early stop had overstated the effect.

• 09

  Fat storage capacity, not body weight alone, drives metabolic risk.

  Weiss uses a bathtub analogy. Each person's genetically set capacity to store fat safely under the skin differs, and overflow into the viscera, muscle, pancreas and pericardium does the damage. People with congenital lipodystrophy or severe insulin resistance have extreme coronary risk; he mentions women needing bypass surgery in their 30s and 40s. Gerald Shulman's insulin-resistant mice got fatter and healthier when given more subcutaneous fat. A DEXA fat-mass ratio (central versus peripheral fat) helps identify this pattern.