May 19, 2015
It started with mild palpitations, sporadic at first, then increasingly frequent and bothersome. Next came chest discomfort, spikes in blood pressure, tremors and a jittery, something-is-not-right sensation the patient described as a “nervous heart.”
For three years, the mystifying spells — lasting from a few minutes to an hour — plagued the 42-year-old Northern European man, sending him to various specialists across three countries and two continents. Full-body CT and MRI scans, renal artery studies, repeat ECGs, and stress and transthoracic echocardiograms turned up nothing. Blood chemistries were completely normal. Yet, the symptoms persisted. Most worrisome of all, the man’s blood pressure went up and down, at times topping 200/100.
When the patient ended up in the care of Miami cardiologist and former Johns Hopkins fellow Juan Rivera, the physician knew it was time to call on Oscar Cingolani, a Johns Hopkins cardiologist with expertise in treatment-resistant hypertension and a knack for cracking hard-to-solve cases.
The years’ worth of clinical notes and medical tests gave Cingolani no clues. But the physical exam pointed to a possible culprit. Palpating the abdomen, Cingolani noticed the man’s fingers turned cyanotic, his heart rate shooting up. He sweated profusely and experienced a flurry of premature atrial and ventricular contractions. Then, in a matter of minutes, the symptoms subsided.
Even though a previous CT scan had shown normal adrenal glands, Cingolani immediately suspected adrenal trouble, most likely caused by a pheochromocytoma. Yet, when a blood test showed normal chromogranin-A values, the plot thickened. Then something else caught Cingolani’s attention: the mildly elevated metanephrine levels of a blood test obtained shortly after the patient’s spell, a finding suggestive of another kind of adrenal mischief. Then a smoking gun: A radioisotopic scan showed a hyperactive zone in the left adrenal medulla, consistent with adrenal hyperplasia. Following a laparoscopic adrenalectomy, the patient’s symptoms vanished rapidly. His improvement was dramatic, Cingolani says.
Isolated adrenal hyperplasia is rare, Cingolani says, often mimicking the symptoms of its more common cousin, pheochromocytoma.
Perhaps more importantly, he says, the condition can also present as stable hypertension, a relatively common scenario within the population that Cingolani treats: those with resistant hypertension.
Most patients with resistant hypertension have essential hypertension, but a fair number harbor underlying pathologies that fuel secondary hypertension.
“Such patients could be easily chalked up as suffering from primary resistant hypertension,” says Cingolani,” when in fact they have correctible conditions such as renal artery stenosis, thyroid disease, obstructive sleep apnea or primary aldosteronism.”
Such underlying disorders, he adds, are by no means the prime suspects in all cases of treatment-defying hypertension, but they are possible culprits that ought to remain on every diagnostician’s differential.
“Then the million-dollar question becomes how far to go and whom to test,” Cingolani says.
Resistant HTN or Something Else?
Defined as the inability to achieve blood pressure below 140/90 mm/Hg despite the concurrent use of three antihypertensive agents (one of which is a diuretic), resistant hypertension affects one in 10 patients with chronically elevated blood pressure.
Nine out of 10 hypertensive patients have essential hypertension, but among those with resistant forms of the disease, about 30 percent might have hypertension secondary to identifiable causes.
There’s no magic algorithm for differentiating between the two groups, and a test that makes perfect sense in one patient can turn out to be a dead-end diagnostic pursuit in another.
In such clinically challenging cases, Oscar Cingolani first rules out pseudo-resistant hypertension caused by medication noncompliance, inadequate BP-measuring technique, or “white-coat syndrome.” To do so, he spends up to an hour in the exam room during first visits, asking probing questions about lifestyles and hobbies and taking repeat BP measurements.
“If the patient appears to have genuine resistance,” he says, “then the question becomes, What’s causing it?”
Once underlying pathologies are ruled out, the most likely culprit behind treatment-resistant hypertension is, well, suboptimal treatment.